Yamaha GT 2000 vs new SL Need advice.

You might never get a verdict from someone who has hands-on experience with both turntables mannye. Mostly to do with the fact that the total numbers of GT 2000 owners outside of Japan is miniscule. More people have been in outer space than the numbers of GT 2000 owners outside of Japan. Let alone those who have lived with both turntables.

Based on specifications only, these are two very comparable turntables, both with coreless motors that I prefer.

In my opinion, if you have your GT2000 fully restored electronically and then calibrated by one of the rare breed that can do it right, you would be on the same footing with a new SL, and perhaps a few thousand dollars richer for not having purchased a new SL.  One would have to do a careful A/B comparison after that, to choose one over the other.  (I am not qualified to choose one over the other, as I have never heard either.) One person who can do the work for you is JP Jones of Fidelis Analog in NYC. I advise you to contact him.

Question I have is if your looking for that last table why not invest in a newer design that will last longer if they are that similar. I've not heard either table but for the dollars I'm sure there is other out there  you should consider. That said I did also go vintage from a modern design and am listening to more music then I did with the $7000 oracle. I went the garrard 301 route but there is others. 

The GT2000 has already lasted ~30 years. Why would it not last another 30 years with proper care and use? Perhaps the bearing will need attention eventually, if it doesn’t already need it, but otherwise....
I do advocate going through the GT2000 thoroughly from the outset, with new electrolytic capacitors, possibly upgrading transistors, calibration of the drive system, attention to the bearing, etc. I am only guessing that this would still be way cheaper than purchasing a new SL. The great revelation of this thread is that in fact we are NOT living dangerously with vintage direct-drive turntables.

The OP’s question is about choosing between one DD and another DD, whereas you made a paradigm shift by going from a suspended belt-drive to a non-suspended idler-drive. Good choice, by the way.

EDIT. In my remark about not living dangerously, I was thinking of the other thread on direct drive, the "living dangerously" thread. Sorry.