Lateral-g Forums - GM Motor help please

I am tearing down the motor I have for my Regal FINALLY and I am trying to figure out what I have.

Story is, my father (mechanic) bought this GM Crate motor for his friend, put it in his van, put about 5000km on the van and then the van rotted away, bought said van for $500 and I have a kick ass motor. My dad thinks it was around 350-375 HP, I drove the van (fullsize) and it had gobs of power.

NOW....

Stripping the motor down and here is what I have so far for numbers

Block- 10066036 which tells me it's a 350, 4bolt, GM crate motor made in mexico good upto 350 HP @ 5700 rpm. It also has 1M0930 on it as well as 5VP...........those are the only other markings on the block.

Heads - Inside the head it says 83417839, GM11 and 286 stamped.............that's it...........can't find squat....

The cam says GM650 on one end and 266 on the other end.

Haven't pulled the crank out yet but it has some pretty mean looking pistons on it.

Any idea where I can find more info ? I googled and most of what I found had no numbers even close to those head numbers, most started with a 3

I want to know what I have before I start replacing stuff for my TPI setup, plus would be good to know the info on the heads so I can get my chip programmed 100% with all the right info.

Thanks