I just put a Comp cam in my side oiler, today in fact! "Dry Fit", assemble crank, rods/pistons, cam, lifters, heads, rockers, etc just to check for clearances and valve train geometry before "final" assembly (coming soon).
But I digress...
I'm using Comp springs that match the cam profile (along with keepers, spacers, etc.). I have dual springs with a third "spring" for dampening. Initially I'll use the single spring to reduce breakin load on the cam lobes. This will allow the lifters to "rotate" in their bore and "seat" nicely to their individual cam lobe. After it's run in and all are seated I'll remove the single springs and re-assemble with the full spring set.
I'll use compressed air to hold the valves in place with the piston at TDC while I use a special tool to depress the single valve spring to remove the keepers, etc. Install ALL the springs and keepers and release air pressure. Go to the next one. Yeah, pain in the butt, long laborius process. Beats the heck out of "flat cam" though!
You MIGHT get lucky and be able to use ALL the springs the first go 'round. But typically THAT is exactly what causes cam lobes to go flat. In about 20 to 30 minutes the lobes are "seated" or "screwed", you'll know pretty quick which it's going to be.
I wonder if your builder would actually do the "two step" to break in the new cam? It is a lot of work, doing cryo might buy "him" a little insurance and avoid the "two step" valve spring break in procedure?
By the way, George from GESSFORD is walking me through this build, HE reommended the "two step"! Who am I to argue with HIM!
PS
My pushrods are to short, gotta order new custom ones. The new pistons are a perfect fit and all other clearances are good to go!