1) I used a 12" piece of 1.5"OD sink drain pipe and cut it in half to make 2 sleeves.
2) The best way to cut it is with one of those small hack saws where the blade sticks out the end of the handle. This will allow you to cut them in half and cut the slots for the reels as well. I have used a utility knife to cut the slots as the drain pipe is not as thick as standard PVC...but obviously caution must be used.
3) To prevent pipe from cracking make sure there is enough play in the slots to put rods in and out yet hold them in place. The reels really don't move much even with a little slop. And when fastening sleeves to bucket, I used 1" 10-24 screws, a flat washer on each side of the screws as well as a lock washer on the nut side. Or you could forego the lock washer and use those nylon lock nuts. Either way, don't tighten down too much...just snug them up. They usually don't come loose. I just check them once in a while.
I have been using them for years and have yet to have one crack or break. Even made some for my tip-ups. Here's a pic that might help. Good luck.