I hate to resurrect the dead but I'd like to know if the OP has completed his install. If so, any finished pics?
I'm working on the same project with 4" GPS speedo; 4" Tach; 2 5/8 oil, volt, and water; and 2" fuel level and fuel pressure. I eliminated the stock radio and relocated it into the glove box and created a custom filler in the console that I mounted the 2" fuel gauges. The console fab is done, the old gauges are out, and I'm just running the wiring and preparing to mount the 5 that go in the stock locations.
Any update would be appreciated.