Where can I find the ground behind the instrument cluster on a late 944?

[uvachief]

I have been having a recurring odometer gremlin with my 86 944 na forever. I had the speedometer replaced several times and I continue to have the problem. Good gear. However, I have noticed a come and go starting problem as well plus some lazy gauges in my instrument cluster. The speedometer works but the odometer does not. The oil and voltage cluster work fine. The temperature gauge is weak and lazy but the fuel gauge works. Someone told me that there is a ground screw holding about 8 wires that tends to get corroded or the wires get separated over time. Perhaps that is causing my problems. I was wondering if any of my fellow Pelicaneers can post a photo of where I might find this particular ground as well as any others that could also be triggering my non-start issue. Seems to be more pervasive when it is hot (temperature expands things) than when it is cold (I rarely ever have a hard cold start issue when it is cold). Any guidance is appreciated!

Also, I forgot to drill screw holes near the steering column before I installed a dash cap. Anyone got a trick to clearing those holes so I can remove the cluster without damaging the dash cap?