I started with a stock 1967 PG from a 1967 Camero 327 car. It has the 1.76 planetary gearset.
Here are some of the upgrades I put in the trans:

FTI-F2520 Input Shaft, 4340 Steel, Turbo Spline, Powerglide. Requires converter have stator centering bushing
FTI-F2543 Lightened Steel Clutch hub, for 6 to 8 clutches
ATI-205642 Steel drum assembly, 7 clutches (8.86 lbs) 0.065” thick, 8 steels 0.060” thick
ATI-205318 Super Servo gapless (hooked) twin rings, gasket, o-ring.
ATI-205750 PG - Springs – Heavy Duty for reverse piston release - Set (17)
SOX-28709 PG HD rear spring retainer
ATI-202100 Shifter Lever, 2-Piece, Steel, Zinc Finish, Chevy, Powerglide, Kit
ATI-206300 Transmission Gaskets, Transmission Overhaul, Seals, Filter. Teflon rings on input shaft & drum support
ATI-203050 ATI Compu-Flow Trans-Brake, external solenoid
FTI-F2553 Transmission Pan, Deep, Aluminum, Natural, 2 qt. Capacity Increase

There are some case mods for the transbrake and durability improvements for racing.
The JW bell is SFI rated for the flywheel/flexplate sheild, but I added a trans case shield to add SFI protection to the rest.