408 Stroker Build Suggestions

A ray of sunshine
Horsepower in in the heads no matter which cu in you come up with the top end HP will be what the heads can provide
the torque below max hp will be more with more cu in
you can add the high buck heads later or get your heads ported later- you want your heads to be pulling their max from low to max rpm
so build the bottom end with a reasonable compression ratio
I much prefer closed chamber so take a look at what's available- that rules out the X and J and 915 even the 308 but you can get some EQ heads for not much more than prep work on the old iron heads- or check out the budget aluminum ones- just stay away from the open chamber ones as as far as I spec you would need KB quench head pistons
of course you could go that rout with stock heads and mill of the quench dome when you changed heads- done that several times just to optimize quench
a consideration is that the later heads have a better combustion chamber- and the 308 is OK
sorry I misread your HFT spec- somewhere I saw HR
set up right I've run 550 lift with stock rockers but no reason to go over .500 with stock type heads-and that's with a good pro valve job otherwise the flatten out at .450 and at .550 you will need custom pushrods with stock rockers
no free lunch
did you post your gears and all the rest?