Removal of rear axle help me!

[ShortBedChevy]

I basically need a new axle on the rear end... I was doing a burnout the other day and i must have stripped out the gears... The weather hasnt been good enough for me to take a peak... but i dont have the tools to adjust the ring and pinion if thats all that went out, and the shop is going to cost me a fortune... So i figured i would call the junk yard, and grab a new axle for my rear end... do the gears have to be the same as the front axles? its 4x4...
Also, how hard is it to remove and install a new axle? im 16... poor... and have limited tools, is this a project i should consider? or park the truck until i get the 1200 the shop is looking for? I could get a new axle for about $150, and then i could drain the fluid out put in a new gasket and synthetic oil, then put it in the truck right? is it hard to do? and do i have to aline the driveshaft up? or just make sure its gears are good?

just now thinking about it.. i could have striped the driveshaft huh? the drifshaft moves, but the rear end wont go anywhere...
what should i do!?
If i take the rear cover off... i will lose all the fluid.. if i do that and decide i need to take it to the shop.. could i just put the cover back on, and keep it in 4x4 and drive the few miles to the shop? or would no fluid in there seize it up? HELP!

[Grim Reaper]

Damn your just full of problems!

Look on the sticker in the glove box. I bet you find G80 on there some where. That's the Gov Lock aka "Granade locker". Burn out usualy smoke them.

If it's toast a axle swap is the way to go. Gears have to match front and rear. On the front diff will be a tag on one of the bolts and it will have the gear ratio. It's probably 3.08 it might be 3.73. Sticker in the glove box also might list it. If that G80 is there it probably is a 3.73.

Pull the cover and on the ring gear (the bigg one) will be some numbers like xxxx 9 41 xxxxxx get those numbers. One of those numbers is the teath on the ring and one is teeth on the pinion. you can figure the gear ratio out from those numbers.