Nicholas,
You have the best version of the A80's ( R ). Workhorses.
VU models are less reliable on the audio side.
Be careful about " recapping " this TR.
Except the electrolytics on the audio power supplies circuits, do not touch the caps used on the equalization circuits, they are precision caps. :!:
An improvement would be to change the range of the pots ( level, bass, high, etc...) that is often way too large or too small, and tricky to adjust.
And use 10 turns trimmer.
Is it a 1/4" or a ( modified) 1/2 inch ?
Guy