Hey, im a new Isuzu owner. Here's my history:

So a couple months back I got an '01 Rodeo 4WD V6 3.2L. Nice price, nice truck. By the second month i had it my abs started acting up, so I pulled the fuse and bought all new tires... problem solved. But, my gas gauge dosn't work, but ive figured out my mileage and have only run out of gas once thankfully. Unfortunately, i need to fix this in order to pass Nor Cal smog. I've heard it's an annoying fix cause you have to drop the tank....

So here comes the questions:

Is there an easy enough way to replace the fuel sensor myself? (I'm assuming this is whats wrong... )
Also... How in the world can i get my back door gate to stop squeaking? lol. I've tried Wd40 with no luck... does anyone have any tips for this?

Thanks.