huge oil leak first time starting new engine

[Vans]

the engine only ran for 2 seconds, and turned over for about a minute priming it, and it spit out about a quart of fresh oil. it was coming from up between the trans and block, so i thought i had forgot to put the oil seperator in the rear main. i just pulled it apart and its in there. im totally stumped.

i know the oil seperator can go in backwards, i had it so the face of it was touching the rear seal and the tabs were pointing towards the block, did i put it in the wrong way? i cant even figure out what its their for and why the seal itself doesn't keep out the oil. the only other thing i can figure is i noticed the rear main seal was just a tiny bit crooked in the housing. i looked at it from an angle and could see on its 9 oclock side there was like a few tenths of an inch inbetween the seal and the housing, could that have caused the hugh leak?

Ive tried searching and someone else had a bad leak like this, it turned out to be his oil galley plug was hand tight. he had to pull the trans to get to it but i dont know what this is. considering i dont know what it is makes me think i might have missed it, so if someone could tell me where and what it is id aprecciate it.

 

[Vans]

ok well i think i found this oil galley plug, because theres a hole i can almost stick my finger in behind the trans plate. i think the machine shop took out the bolt and didnt put it back, and i just missed it.
so i guess this kinda answers my own post put maybe this will help someone else