1988 90 Quattro niggles

[Nick_S]

Just got myself a 1988 90 Quattro with a KV powerhouse. It's done 152,000 miles with a full service history.

Any pointers to help me out with the running issues?

Temp indicator comes on even though not overheating
Amber coolant overflow? comes on
ABS not working, have to disengage to drive car safely.
Misfire at high RPM.

Hopefully these are straight forward enough for me to fix myself. There is a F plate coupe in my local breakers i could get the expansion tank from?

Much appreciated

Nick.