I purchased a V2 mini off of ebay as a parts printer and after a few repairs it's as good as new, however the x-axis end stop switch post was broken on the original carriage. I also found out the mount for the lead screw was integrated into the carriage design so you can't add a nema 17 motor without replacing the carriage. This helped in both areas for me.
I'm not the original designer, just modified it for my preferences. I integrated an end stop switch bracket, cut down the one side to accept the standard 35mm bearings (length), enlarged the bearing holes and thickened the mounting plates for the nema 17 motor and the lead screw nut. The original was two piece design and I made it into a one piece design.
I used petg with 100% infill for structural integrity.
Added a second z carriage, listing as V2 specific, it's in the correct orientation to print. My original model was remixed stating that the bearing holes were misaligned. Since I have the original working file it was much easier for me to correct. The holes were a bit off I admit, now they are perfectly aligned. I also modified the model so you can use a M3 nut and bolt to secure X axis rods rather than gluing them in. The model integrates the x axis switch so you can remove that terrible noisy X axis cover. The remix removes the integrated switch mount and adds the mount for that cover (don’t know why you would want to do that) but you can check out the remix for that, infill is up to you.