Which would be better to cool the hot engine oil before it reaches the turbo or after the turbo? If after do I need a scavenger pump to help it go thru the cooler then back to the pan?

 

You could do either, but probably makes more sense to cool after, and would need a pump.

 

I would be putting the pump after the cooler then? I know there are quite a few different pumps out there but, would they be strong enough to move the oil anywhere in the engine? I was thinking of dumping the oil back into the engine thru the galley plate under the intake.

 

Pump would scavenge oil from turbo, and pump it thru the cooler on its way back to the engine. There should be very little resistance to flow, so the valley plate should be fine. Only drawback is oil returning over the rotating assembly.