Vintage DD turntables. Are we living dangerously?

This has been discussed elsewhere, possibly earlier on this thread. The TT801 is essentially a TT101 with vacuum hold-down. To incorporate the vacuum system, it seems Victor used, or would have had to use, more ICs, to replace discrete transistors in the electronics section, than were used in the TT101, because there is much less space in the TT801 chassis for PCBs than there is in the TT101 chassis. There is a nice cutaway depiction of the TT801 on Vintage Knob that shows how much plumbing was incorporated into the TT801, even though the vacuum pump itself is housed separately. If one wanted vacuum hold down on the TT101, one might be better off to find and restore one of those vacuum mats made by AT, although I understand that restoration of those is problematic, at best.

I am using a Home Designed Purpose Produced Rack for my TT Set Up, and the Top Shelf has an assembly of Tiers built on it, to offer the TT a good foundation to perform on.
The AT-616 Pneumatic Feet have a permanent place in the assembly.
They were the Icing on the Cake for a good period of time.

I have used them for many years and today they are resident under a Sub Plinth for the TT and Solid Tech ’Feet of Silence’ are used under the TT’s Plinth.

The AT-616 have been tried out on visits to other HiFi owners homes and in one case used under Speakers belonging to a friend who was finalising a Decision to buy Townshend Isolation Bases for them.

I heard the Speakers with both the AT’s and as well when Two versions of the Townshend’s were put to use, was equally impressed by the improvements to the presentation from each Support.

The Solid Tech’s to my perception have the most impressive affect on a TT, hence why they are in direct contact with the TT’s Plinth.
I also like the idea that I can play with the Suspension Configurations, and the Weight Load contact points on these, in a way that the use different Materials or Different Diameter Materials can be utilized to produce a slight variant of a attenuation.

The Solid Tech’s have also been out more than the AT’s on home visits to other HiFi Enthusiasts and have been quite successful at creating a good impression for the other TT Owners when used on their TT’s in their own homes.

They Triggered Off my Local HiFi Groups Search for a more affordable challenger to be used for the same purpose.
I know there are Isoacoustic GAIA in use on at least two of the systems at present.

One friend took it to the extreme and produced a Platform based on the Design Principle for his TT.

I'll be using TT101 with original plinth and the AT-616's. Waiting for JP to receive my saucer and do his magic. Then off to Miami to sit in newly veneered original two arm plinth. The AT-616's are super cool looking too. 
@pindac

I am as well experiencing a similar excitement for Vintage DD's,
I have been slowly bringing a Plan to the forefront to be undertaken

As part of my owned, but not used 'Daily' TT;s I have 2x TTS-8000
2x DP-80 and 2x Aurex SR-510;s.

I have a design in place to exchange an amount of the Original used parts on the TTS 8000 with a seen to be improved materials.

Some the most important exchanged components are to be produced in Duplicate from similar materials that are composites, and known for their stability to perform without change in any ambient environment and will remain unchanged in their properties when used on a TT.
The Duplicate Parts with have a variance in their Shore Hardness Scales readings, these Parts will then further allow for a fine tuning of a Attenuation when the TT is set up in its permanent set up.

The End User will (if wanted) be able to make some slight alterations to the Presentation of the TT, by swapping out a Part that has a Identical composite of materials, but produced to have a change in a property at the time of Manufacture to be a material that can be optimised for certain types of application.

I can then make a plan for the Other TT's if this Design Change to the
TT-8000 is seen as a improvement over the standard model.
As I am not seeing any restrictions on any of the the Stripped Back TT's that suggest the TTS redesign is limited to that model only.

There is a Plinth design Drawn Up as well, which is going to allow for a TT to be mounted in a Plinth that can be inserted into a Substantial Permali Support, in which the Tonearm is attached to.
This will allow for the TT Trials -
Original Model vs Exchanged Parts Model - to be carried out in with the exact same Tonearm Cartridge and be exposed to an identical Impact from the Ambient Environment.

When all this intention comes to fruit, and I have selected DD TT's from the group that have been the most impressive.
I can then produce a Plinth to be inserted for my other TT's be it Idler or Belt and carry on with a furthering of the comparison trials.

Obviously the above has a not so common approach to a
Preparation and Investigation into a Experimentation with a whole range of TT's used in a Standardised Set Up.

One of the parts used in the Standardised Set Up will be one of my sets of the AT-616 Pneumatic Footers, as these have lest a good impression on me for a Long Time    

Have a question for you experts, just remember I am learning about analog and some things I might get it wrong.
Just recently acquired a PD-444, the ability of mounting 2 tonearms and looked in good condition it made it hard to pass by, still waiting for it to be delivered. I've got an EPA-100 mk2 for it with an SH-100, as I understand it this is a Medium to High mass tonearm which would benefit from moderate to low compliance cartridges.
For alignment, what do you guys recommend? the tonearm original mounting template is at $120 on Ebay which is nice but a racket IMO. I've got the protractor that comes with the Hifi News record but seems to be Bearwalds whether this specific and most japanese arms are Stevenson.
Raul posted that some tonerarm alignments even the manufacturer got it wrong (was it Saec?)
So my question would be which type of alignment should I follow?
P2S is 250mm and Overhang 15mm
Any specific method to test the bearings?
Any cartridge recommended for it?
As a second tonearm for the PD-444 what should I look for? MA-505LS? FR-64s or 66s? apparently the SAEC's and Victors are not that good as the FR and MA per previous comments. Just trying to look for a versatile tonearm different than the EPA-100?Note I also have a 1200mk5 Technics with medium mass tonearm.
Thank you in advance for your answers, I'm excited with learning and rediscovering vinyl.
Raul, looking forward to your comments (bad or good) I won't complain, your experience is legendary
Chak, of course I'm interested on your comments tooLew and Nandric, I respect you immensely, you guys make a lot of sense.
All the best
Luis