More Blazer questions

Ok, I suppose by now everyone thinks i'm a complete idiot, but help an idiot out.

I have a 91 S-10 Blazer with a 4.3 FI that has 191,000 on the clock. Just finished putting in a water pump, took it out for a drive, had it goin about 50 max (unregistered, don't want to run it down the highway)...just wondering where the temp gauge levels out, it seemed like it was slowly creeping up to overheating. Also, as soon as the truck slows down or I lift my foot off the gas the oil pressure skyrockets...I mean maxs out, and then drops when i hit the gas again. I know it has an oil leak that I think is from the pan (havn't looked closely yet).

Then, I hit a bump and the digital dash goes bye bye. The kid i bought it from told me this would happen because he took the radio out and half ass taped off the wires so if they touch right it pops and just to change the fuse under the dash...but i pulled every fuse and none were blown so stupid question number 3....which fuse controls the digital dash? I don't have a cover or really anything that tells me which fuse is which.

I think thats all for now...lol...

based on what you are saying about the wiring, i wouldnt trust any of the dash gauges...

install some aftermarket gauges, or at least get some testers to see what is really going on... a properly functioning cooling system should prob run around the rated temp of the thermostat, ie 195ish i believe.