oil pump drive?

[95suburb]

I took out my old oil pump drive from my original engine that had 174,000 miles. I just got another 6.5 that was taken out of a hummer that has between 10-40,000 miles. When I put the oil pump drive back in does it have to be put in a certain way or lined up with anything? Or do I just plug it in. Also, this engine has a compression of 500 in every cylinder and holds 50lbs of oil pressure at idle. Is this a fairly new engine?

[94K30]

in GM shop manual, it says "1)New gasket on oil pump drive,2) Oil pump drive into the engine, index the drive onto camshaft gear, and oil pump drive shaft, make sure it seats fully, 4) clamp and bolt. it would seem that is is very similal to a standard GM V-8, the oil pump has a slot in it ( kinda like a big standard screw) and there is a tip on the drive that is driven by camshaft ( like the distributor in a gasser) and that drives the oil pump. as long as you engage the camshaft, and the slot lines up, you should be good to go.
I have seen those engines advertized, and would be interested to hear how it works out for you.....
Marc