Linn lp 12 upgrade or new TT ? please help.

I added a lingo at a cost of around $ 600.00 and think it was a great improvement.

Get a new, thinner mat. I forgot to say that I am ordering one. Martin Colloms, who has used the LP 12 for 20 years recently changed and said it was the best improvement for the price he has ever made. My Linn is also from the 80s and I am also changing the belt and oil. I am ordering the mat from a shop in Scotland I found on ebay as I couldn't find the mat on sites here.

New. Upgrade is a costly route that will generally not produce the same change.

Lingo = yes
Cirkus/trampoline = no
Belt change = yes
New mat = yes

Since you are going down the upgrade road, you should also seriously consider an upgrade in the power supply. If the lingo seems expensive, Origin Live make their own separate (external) power supply that also fits the Sondek. It comes in three different guises to suit different pockets; have not heard it myself but got some sterling feedback from other Linn users. If that does not fit the bill, do try the Herc upgrade. Trust me, sound wise, it is worth the outlay over the Nirvana.