Ok you know the rules, must use at least the Fox 35 crankcase and must remain plain bushing. Here we go:

Crankcase Fox 35, 50th or 60th anniversary for most metal. Head and backplate bolts tapped 5-40 and motor mount lugs machined flat for pan mount

Piston and sleeve, SuperTiger G21-29 ABC  will fit by taking .010" off the OD

Conrod, 7075-T6 custom length and bushed with phosphor bronze.

No more baffle so head can be billet hemi with turbo plug and generously finned for cooling (plain bushing runs hot)

Crank, custom solid 4130 shaft no timing hole, full circle crank web and counter balance with extended crank pin

Back plate, billet rear valve with SuperTiger disk timing 35/60

Venturi, 5/16" with SuperTiger NVA


Your turn,
MM

There's a whole AMA Rule Book full of events where you can build an engine and not be hindered by the Fix case.

i have plans for a supercharger

Supercharges are legal.  Just not compressed gas cylinders.