Tips on replacing and/or screwing with the oil pressure sensor '96 5.7L Vortec

[sparkydog]

The truck in my avatar is basically a stock '96 GM truck just with a different skin over the top of it. I am ready to stop using the 96 GM instrument cluster and convert over to Autometer gauges so that my dash looks more like a 60's truck.

Part of this task is to mess with the GM oil pressure sensor so that my Autometer gauge will read correctly.

Now for the hard part. The oil press sender on a 96 Vortec is on the top rear of the block beside the dizzy and it is going to be real hard to access that area. (Firewall is also stock 96 GM so it's just as cramped on my truck as it is on all of yours!)

If I could reach back there and remove the GM sender it is a 3-wire combo sender and switch that involves the fuel pump (or so I read). So I would need to either replace the sender and jumper the 2 wires involved with the fuel pump and just use the tan wire for the gauge signal or...

put my new Autometer sender in the spare oil port on the side of the block above the oil filter. However - even if I do this (because it is easier to access) I still want to tie the signal into the tan wire that is up there on the rear of the block.

Does anyone have experience with reaching back there to replace the sender? How did you do it? And has anyone jumper'd the fuel pump circuit like I am talking about?

Edit: PS here are some shots of what the guts of your instrument clusters look like!