90 degree adapter leak

I have had this same issue. I had a 90 adaptor on my 418 and it leaked all over when I got on it. Last week I changed to just the filter plate and it still leaked. After reading this forum I ordered the Canton Filter plate with the O ring. I put it on last night, cleaned / scraped block surface again, torqued to 40 ft lbs and It still leaks!
Has anyone had sucess with the canton plate? Im wondering if the o ring moved while tighteningcause it did spin some. Or is that o ring just not give a good seal. I'm running out of ideas here and sick of the leak!
I have a high volume pump and have @ 60 lbs pressure at higher rpm. Doesnt seem to leak at idle even though it has 80 psi cold. It seems to leak when I get on it as thats when I see the white smoke in the rear view - burning off the headers. There is oil all over on the filter side and I cant believe it would be coming from anywhere else. Thanks Tom