Centurion clutch

[LRDG]

I'm a bit worried about this one. I'm doing a bare minimum clutch install on a Centurion. The original clutch pressure plates, including the clamping plate (aka end cover) and friction plates are shot. The pressure plates and the clamping plate have some serious heat cracking and corrosion and the friction plates are torn up and embedded with rust from the corroded pressure plates.

A spare clutch we have has non-cracked pressure plates and clamping plate and not-bad-after-clean-up friction plates so I have swapped them into the original clutch. What worries me is how the original assembly was balanced. I've installed the spare clamping plate (end cover) on the original housing, and I see the potential for horrendous unbalance if they were NOT balanced individually but as an assembly.

I'll try to do a simple single-plane balance on the assembly on knife edges but does anybody know if the variojus clutch parts were individually balanced before assembly? If they were, I'll be less worried about mixing and matching.