Can anyone give me a good step by step on changing out the rear main seal? Its a 1988, so its gonna be 1 piece design

 

Pull driveshaft

pull trans

pull clutch or TC

pull flywheel/flexplate

rip out old seal w/seal puller

tap new seal in

everything else in reverse order.

 

While you are "there"...
Say hello to the rear cam shaft seal, too.
Replace that now. It's right above the rear main seal.....
Never hurts to use some gas-a-chinch on the seals......
PS Buy the best gaskets/seals you feel you can. GM gasket product ain't bad stuff right now...
Classify this as a pure joy a minute mission.
I'd make sure do not need tranny rebuild same time, only to discover later on, you "did" and need remove all this again.....

 

I'm just selling the car, but i gotta have it running before i can get decent money for it.

 

The other gasket is like also $3 - $5 range & seriously you'll find it also leaking & IF ya wanna sell the car it being leak free is a good thing.
Get them both I mean the opportunity for easy replacement will be in your hands
Shame you have to sell ride after sealing those things up.
Those two items are number one on leaks for these engines.