98chvytnk

so i have a pinion seal leak AND a p/s axle seal leak. I know that there is a 'rod' in there that if you strip it then you're pretty much f'd and can't get the gears out to change the seal out and have to get a new axle. but i'm going to tackle that myself. if i can change the motor i can probably do this? ya or na?? also, i've read in a few places that the diff fluid needs to be a certain type for chevys. mine is a daily driver but i like to take it back in the trails quite often. any ideas? i'm in nw florida so heat is def a issue.

thanks yall

Adam