With the tacho problem, i'd get a mate with a cluster and just do a quick swap to test. Most likely it's not the cluster but better to try that before forking out for something more exxy. If the problem's still there, then i'd be looking into the dizzy. Same shit, get a mate with a dizzy, swap it, adjust timing and test.

Defs change thermo for the other problem as mentioned, dc2 thermos fuk up more than ben cousins.