DAVE - You mean the output shaft size? The early H's used a 1-1/8" 6-spline, M's got the 1-3/8" 6-spline SAE standard. The CC's and I think the FARMALL CUB used a 15/16" multiple spline, seems like it was ten or fifteen splines. Cub Farmall turned the correct way, CC's turned "backwards" due to the reduction gearbox, or counter-clock-wise.
Not sure which way the tiller gearbox would turn if turned 90 degrees like Norm's pic shows.
I think it was at the RPRU in Sandwich years ago that someone had a 2-blade timed deck from a '61/'63 CC modified to run off the rear PTO kinda like a pull-type bush hog. I think KRAIG has a pic of it in his files.
CHARLIE - I've seen almost ALL attachments for CC's, at least pictures of them, but THAT Chain Broom is something I've NEVER seen before. It must be even more rare than the M&W frt mounted weed mower.