I just now got to use the freewheel/brake adapter and the brake adapter I purchased back in 12. I bolted the disc to the brake adapter without issue. I went to bolt the disc onto the freewheel adapter and I couldn't get any of the bolts to start. I pride myself on being pretty handy so I thought I wasn't starting them right and was maybe cross threading so I checked the angle spun them backwards a little to seat the bolt and tried again but no luck. Nothing I did worked, then I thought the threads might be a little rough so I tried to find my 5mm tap so I could chase out the threads but couldn't find it so off to the hardware store I went. They didn't have a tap for 5mm so I went off the nuts and bolts aisle 15 to find a hardened bolt to try to clean out the threads. In the better light of the store I noticed that the threaded holes looked a little small, I grabbed a 4mm bolt and sure enough it fit perfect. The print said 5mm but the machinist had drilled and tapped the holes in 4mm instead of 5 like the brake adapter. An hour and a half and $2.86 for 4mm bolts and a 2.5mm allen wrench and I got it done. Wow, this trike is going to take me forever to finish.