Rear main seal is setting in the block uneven?

I purchased a 2000 ford ranger with a 3.0 flex fuel V6. The engine spun a rod bearing and I picked up another engine at the salvage. Anyways, the rear main seal on the salvaged engine is setting in crooked. The bottom is about an 1/8 of an inch further in than the top. I really don't want to replace it. I tipped the engine back to see if oil leaks… It doesn't. So, do you think its alright to slap it in or do I need to replace the rear main seal? Again, there's NO leaks…

I would call the junkyard to find out if they have another engine first, if not, then change it, you've already got the engine out of the vehicle so it's not the hardest thing to replace. If nothing else, buy the rear main seal installer and press it in properly (or you can GENTLY tap it in with a 2x4 and a hammer working in a star pattern), but there's most likely a reason it isn't seated properly (possibly because it was done with a 2x4 and a hammer…). I'd rather spend the 20 minutes replacing it than find out 10 miles up the road you need to replace it. Either way, good luck.

Just because it doesn't leak now, in a static, non running mode, doesn't mean it won't stream oil when that crankshaft starts spinning. I'd replace it and make sure it's right.