Thanks but think I nailed it.  

Thanks for the replies. Funny that Bing says the opposite but what you all say makes sense to me.

looks like they're both about 81.9 mm.

Thanks. I will check the diameter. Can't read any stamps on piston head.

Thanks. Didn't see them but I think Randy Long (Long's Mechanical Service) in PA will do it for me. We talked a while today and his price was right if...

Yea I was afraid of that.  

I think his mechanic told him. I’ve since pulled gear box, clutch and fly wheel. Basically complete inspection.

clutch wear pattern odd to me.  IMG_9343.jpeg

other side of FW  IMG_9352.jpeg