1971 a833 flywheel/clutch size

the O D of that flywheel is 13. 3 inches. you can use a 10.95 disc under the 10 1/2 pressure plate.

No. "Not that simple." It has to be a special pressure plate MADE for that purpose, normally known as "scalloped." There are threads here on this subject. My old 70 440-6 used that setup they are troublesome, or were then. The outer edge of the disk "fuzzes up" and it won't release "clean."