Hopefully this helps someone in the future. I have a 1990 Iroc Convertible that I swapped an LS1/T56 combo. I used a Hawk's kit and one of Pocket's custom harnesses. Up to about a month ago everything was running fine, then one day while driving the gauges stopped working and the gauge fuse was blown and kept blowing the fuse. I researched for weeks on the forum, tore the dash, replaced the blinker lever, lever cam, tried disconnecting all lights and other connections under the dash etc etc. I did everything that I saw on the forum could be the culprit of the short, nothing. I took it to a local shop and after a few days they found the short. One of the Four o2 sensors, the front driver side, was dented and wires shorted. They disconnected the sensor and fixed.

I thought I would share in case someone runs across the same problem. Something else to look at.