[88 Beater]

I was thinking the same thing about it being in the cluster but I've spent a bunch of time on it. I can't find any obvious problems with it and everything else on it works. I also took the cluster out and checked for any shorts or breaks in the wiring between there and the ECM plug. All seems good.

I've done a little checking of the grounds and no problems there so far. The positive batt cable probably does need replacing. It's been hacked into and is a little corroded. I guess fixing that is worth a try since it needs to be done anyway.

The truck is running a little better than it did with the previous ECM but still pretty rough. This truck belongs to my brother in law and it's been neglected for quite a while. I know it hasn't been running well for a while either. It probably has multiple issues but I figured this is as good as anywhere to start. I'd probably chase my tail for quite a while trying to fix a truck with a bad ECM so I just want to make sure it's good before I proceed.