first, the blower would run counter clockwise (based on the blower chasis I just looked at in my garage), second, unlikely you'd find a bucket wide enough, a big walk behind is 36 inches or so, which I bet is to narrow for behind a tractor.
Besides that, I bet it would be easy to rig up.
PTO shaft with knuckle at either end, weld one end to the pulley on the blower and the other end would have standard 6 spline to slide onto tractor
pto and then weld up quick frame with angle iron for 3 point.
RPM is a good question on the bucket pulley for the blower. Based on really rough math, 10 inch pulley on bucket and 2 inch pulley on engine shaft would give you around 700
rpm I think at 3500 engine
rpm which most walk behind snowblower motors run at full throttle.
Your 540 maybe a tad slow.
Interesting idea, I really think the problem would be width of blower bucket.
Joel