I have a freshly rebuilt 2.0 and the oil cooler seals keep popping. I'm on my 3rd set and the lower one just started to go again. It's not a slow leak either.

I have tried to install them dry, or with sealer, but they keep going. Seems to be after a spirited drive.

Any tips and tricks? I'm pulling the engine this time.

What do you mean by popping ?

Did you take a long hard look at the oil pressure sender ? That's the usual place for a leak and it makes it look like the oil cooler seals are leaking.

Is it possible your oil cooler itself is leaking?

Where are the flat washers that go on the cooler studs before the nuts?
Some people have mistakenly installed them under the cooler instead of after the cooler.

check sender first, it looks like a cooler leak.

But if it's not that I have run across a couple of coolers where a DAPG, as in Dumb Ass Previous Gorilla, who's never heard of the term "torque wrench", has way over torqued the cooler and has bent it (maybe cracked) to the point that it will never seal.

Cooler seals shouldn't have sealant on them.

Well the last two times I could see a clear deformation of the seals. First the upper, the second time the lower. The sender has been checked as well and it's dry.

It could be that the cooler itself is bent or something to that effect.

They are all there in the right spot. Not used as a "spacer" so to speak.