I would hold the camshaft verticle with the gear towards the ground (close to the ground), heat it up evenly w/your mapp gas, & when it is heated enough, the gear will literally fall off.

Apply the heat towards the center, not on the teeth.

Remember Toms turbo dyno 250 was only running 5 psi of boost pressure to make 350 HP, I think you are going to run more than 5 psi?

I think if Tom sold you the springs & he is going to set-up your cyl head, he should know how to set it all up.
You should talk it over w/Tom since he is doing the work.

As far as ARP main & head studs.

For you being turbocharged & you are going to push it , I would recommend the head studs @ a minimum.
The studs will give you a better clamping force than stock head bolts. less likely to blow a head gasket w/ARP head studs.

Are you going to use a Felpro 1025 gasket or a MLS head gasket?
Example: http://www.ebay.com/itm/201113338861?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649


As far as the main cap hardware, I think you can get by using the stock bolts, maybe someone else might recommend them.

I never blown up a 6 cyl yet, not saying it can't happen.
I used to run to 6500-7500 RPM range on stock main cap bolts.

MBHD

12 port SDS EFI