Oil down below?

Is anyone else leaking oil now that they are running 33's without regearing? I know it's stressing the motor, but would it be causing it to leak worse?

where is it coming from? Oil pan, rear main, oil filter, valve cover? Fix it

That's the thing. I thinkit is rear main. What does it take to replace the rear main seal?

Its kind of a PITA but it needs to be done, I did mine on my 87 and Im 99% sure its the same. Go to the parts store and get a new seal, its only like $12 or so. While your there get hanes or chiltons repair manual and it willl walk you through it. You have to drop the oil pan so youll need a new oil pan gasket also or just buy some TRV silicone instead. IT will take quite a while to do so make sure you allow for that. To do it yourself itll cost, $12 for seal-$8 for silicone, $12 for new oil, and $3 oil filter.
The dealer will charge you about 400-500