05 6L died cranks no start
 

Was driving down road hit a pretty bad bump truck died turns over but does not start had it towed to shop mechanic checked for codes nothing came up checked the high pressure oil and was only getting 45 psi so he changed the ipr valve still won't start so he changed the hpop now and it still won't start now he's thinking that it might be the low pressure oil pump any other ideas

Get another mechanic. You cannot just throw parts at something and engine.
So was it desired icp being 45psi, or was it just the actual icp? Make sure the FICM is plugged in tight as well..

It was actual pressure, and now he says there is nothing at all after the new hpop is installed

What was the desired pressures at?

I'm thinking low pressure oil pump too, bump was just unfortunate coincidence. You better test low pressure oil pump first, and check for shavings in oil filter housing.

So after all that it was number 6 injector blew top oring out, swapt injector out and now it runs perfect.

That can do that for sure!
Congrats on having your truck back.