2 Questions in one post

[rockman20]

First off, how can I tell what kind of sending unit I have in my fuel tanks? I want to replace the HUGE fuel gauge in my dash with a small Autometer gauge and then put a tach where the fuel was. Can I just put a digital multimeter on the gauge and have one tank empty and one tank full and test the ohms on the empty tank and then flip to the full tank and test the ohms there? Then I should be able to get a gauge to match those ohms right?



Second question deals with gearing. I want to put 3.73 in my pickup to get rid of the 3.40's that are in there right now. It should help my towing power. Now, I have never touched a rear before so bear with me. How hard is this to do? I have pulled axles and the carrier assembly out of a S10, but never replaced the ring gear or anything like that. I just worry about the backlash and such. How hard is that to get right? What all do I need to know about the rear? Right now I know that it is a 10 bolt. I have pulled the cover and checked. Am I safe to assume that the front is a 10 bolt then as well? (I know that if I replace the back, I need to replace the front) I have been toying with the idea of posi to help with the off road use this pickup sees as well. Would you use posi on a vehicle that is mainly a tow vehicle but does see off road use primarily in the winter months. Can I put posi in the rear and not in the front? Or should I put posi in the front and leave the rear? Or would you do both?

Okay so the second question is actually a bunch of questions!