I'm struggling with my new 500cid low deck stroker moror. I have a big oil pan leak from the front right corner and in the area of the rear main seal retainer. The Engine is equipped with a Milodoon Road race pan (part# 31580) and a windage tray. Frist thing I checked was if it leaked from the rear main seal but nothing comes out that way.
I have checked alignment and height of both front timing cover and rear mail seal retainer and that seem to be ok. I have used gaskets from Superformance two times now, once dry and once with small amount of High temp RTV where the timing cover meets the block and the same with the rear seal retainer. The pan is not warped and is 100% flat. As soon as the engine gets warm and gets reved above 3000rpm it starts leaking.
I'm running an open air filter style valve cover breathers on both vale covers but it still shows signs of crank case pressure with the deep stick raising out of it's tube. When I rev the hot engine without the breather I feel a slight pressure coming out of the breather grommet in the valve cover. The engine is freshly built professionally so I'm doubtful to piston ring blow by.

The oil leak is driving me crazy and I wonder if there is anything I could I have missed out? I consider trying to set it up with a vacuum pump, thoughts on that for a street motor?