I have forgotten more about clutches than you will ever learn, thank you very much.
As I said, junk is JUNK at any price. BTW, I use a Sof-Lok in a DD and drive it all the time. So does my wife.
If it's a stock or even a warmed over 273 then you can use a factory clutch.
As I said, a diaphram is a contraception device. That is all.
Or, if you are a cheep ***, you can make one as a pressure plate cover. That's why they are so popular. They are cheep to make, nonadjustable, and virtually worthless for anything but a stock application. Again, if it's for a stock application 273, use a stocker.
Geebus you guys love to justify spending bad money and convincing other guys to do it too.