PRM? They were a bumper and skid plate kind of company. RPM is the axle company.
Tusk, Vitos, and the low end DuraBlue would be about the same. Upper end DuraBlue and Lonestar are next up. RPM would be the best you could buy as far as trail and Moto type axles.
You should be able to put them on and run a normal banshee piston instead of the typical Weisco 795 piston. I'd suggest getting a few different base gaskets to mock it up and see where it sits the best.
Just curious if anyone has happened to buy ARP studs to replace the OEM studs. With the cost of the OEM's vs. ARP the cost is about he same. I figure it would make sense to switch if the ARP's are stronger.
It's for a high compression short track motor with a super duty head. I used to run an old girdle head and switched to a one piece super duty head, but found the new weak spot was OEM studs.
Pipes, porting, compression, timing, and stroke all play a factor in what the RPM will be. Just let it eat and make sure you're feeding it enough fuel.
If it's not some expensive billit crank, use a box end wrench to loosen the timing plate bolts. Split the cases and toss the crank and flywheel in the trash.