Wow, I don't look for 2 days and there's an explosion of content !
Leon - thanks for your offer, but I have several plates, all rubbish because the part that should be flat on the outside of the dish is... you guessed it - dished itself.
Now, I might be old fashioned, but when a steel clutch plate has to contact a flat friction plate, I prefer it to be flat too
In my opinion, it is a design flaw to make a steel plate that will distort when it gets hot so that it is no longer serviceable, and all the plates I have show that sign. So the plates might have been very clever to fit into a small space, back in the day when you could get new ones whenever you wanted, but today they are crap.
Also, I am a rudge club member, and I have the drawings for M2062x5 and its design thickness, from the drawing, is 16G = 0.064"
So !
Eureka !
I think you may have some that were made such that they resist heat distortion !
As in exactly what a race dept would do without telling the public
1/8" nominal will definitely be more robust than 1/16" nominal !
And as far as swapping parts from one manufacturer to another goes... back in the day, they would do just whatever they thought might be helpful... just as we should be prepared to do today if it means keeping an old clunker on the road rather than as just a pretty museum piece
I'd still 'just' like to get some new standard-ish steels though