You should be able to remove the pan without lifting the engine. Might have to rotate the crank. If your engine still has the original rope seal it's time to do that also while you're under there.
Sounds like you need a reverse manual 400 with a gear vendors OD. If you're killing 200's at 18psi there's something not right. What did EA say when you talked with them?
Hopefully they aren't just labeled that way. The AC Delco looks decent also. I loaded up on US made Wix ones when I thought they were switching to Chinese production. You can still get them which is good to know even though I think I'm covered until I'm in my 70's.
Guess which one is made in the US? I heard both are good, the China ones are no bueno.
To the OP where is the AC Delco made? I asked and didn't get an answer.
Don't be worried, be patient. When's the last time you contacted him? Everytime I contacted him he got back to me within a day or two. He just emailed me today.