The thin frictions are roughly the same thickness as the steels. The friction in that pic look much thicker.
4 x .086 = .344
4 x .068 = .272
total .616
5x .061 = .305
5x .068 = .340
total .645
It's a .030 difference loading the drum. Never had to machine a 4 clutch drum to put 5 clutches in using the thin frictions. You must you both thin frictions and steels.
I don't let vasoline or assembly lube into the clutch pack itself. Lube up the sealing surfaces and wipe any excess away. Drop the in steels/frictions dry, measure/adjust clearance. After that, soak frictions and drop in with dry steels.
