1. Y-axis parts info

Could not do the upgrade, wasted 1h. At step 7 the nut is not supposed to be able to rotated freely in the part. It did in my part. Missed this and thus I was not able to finish step 11. Not a good experience. Had to undo the upgrade and use the old part which was snug enough to catch the nut. Not a good experience at all

I'm using the modified part which is better than what Prusa provide (https://www.printables.com/model/814369-mk4-y-axis-overhaul-reduce-vertical-artifacts-on-y)- I guess I'll have to reprint the parts to ASA instead of originally PETG. 

Always keep the old parts just in case (see comment on the tensioner steps below)

I had to reprint these parts recently (prior to upgrade to 4S). When I did, I used Prusa PC-CF for them.
Are these the same design as in the Mk4 build and the only difference is that they're PC-CF, or is it a different design? Meaning, should I use the included parts if I've already printed the Mk4 version in PC-CF?
TIA, Erik

My PC upgraded parts cracked (belt tensioner) and broke during the install.... anyone else have this issue?