stock or hv oil pump

Yes it will, but you have to pound some clearance for it to fit.... I test fit it on the back and get it to sit flat on the block without a gasket to make sure that the high volume oil pump doesn't keep the pan from sealing...

Just get out the old ball peen hammer and bang at the back radius and back surface until you get it to sit flat and line up the mounting holes...

Sometimes. It depends on which pan and which pump. I've had them fit right on before and then had to modify the pan.