I guess there was more to this thread than just which crank to use

Really the Stealth heads are pretty small for either stroke length, so as mentioned earlier the small difference in stroke is not a big deal. On my 505" stroker, I only used the Stealth head because I wanted the stock look and the engine will not be turning high RPM levels. I have the earlier stealth castings and they cc at 84cc as advertised. For comparison, my smaller 500" stroker has Max wedge port sized Edelbrock Victor heads, but this engine can see 7,000+ RPM.

The parts Hughes suggested can work, but with 80cc heads and zero deck pistons, the static compression ratio is fairly high (about 11.79:1)
With a cam intake closing point of 70-degrees (a cam that has advertised duration around 290ish), ABDC, cranking cylinder pressure should be about 180 PSI.

The biggest difference I see between using a 4.15" kit and the 4.25" kit is that the stack-up of the stroke, rod length, and piston compression height of the 4.15" kit puts the piston slightly lower below the deck height than the 4.25" kit, so you would have to cut the block a bit more (about 0.010" more than the 4.25" kit) to get the pistons at zero deck?

It is also easier to lower your compression ratio than increase it. Without changing the quench distance, you can work the chambers of the heads to unshroud the valves and polish the combustion chambers. The piston valve notches can be enlarged. As mentioned earlier, "D" cup dish pistons can be used. You could also not zero deck the block. Having the piston 0.006" below deck with a 4.375" bore is 1.478cc added to the chamber volume. Using a 4.50" bore gasket adds 0.413cc compared to a 4.410 " bore head gasket of the same thickness.
Just having 84cc chamber heads vs 80cc will lower the compression ratio to 11.35:1 and with the same 70 ABDC intake closing point, cranking pressure drops to 171 PSI.

I would guess the Hughes HEH5055 cam would have peak power around 5500 RPM? in a 500" stroker?

If you do want to use a milider cam, then you would want to drop the compression.