Hi Evan. I did not build my 601. I'm about the 4th owner. My "kit" was apparently built in the Czech Republic so every time I call Zenith about parts I get "we're not sure it will fit, you need to speak with Rodger." He had me measure the bolt pattern on my existing wheels. It was a bit different than the current Matco wheels/brakes. I told my mechanic and he said he would be able to get them to work. He did need to have some parts made but he got them to work. I usually work alongside him but because this was a "long" project having to get the parts made, I did not see exactly what was done. I did have to pay $1400 for the parts and labor not to mention $900 for the wheels, brakes and tires. On the plus side thew new brakes work much better and I can actually hold the plane still while I do my run up. I'll speak with my mechanic and find out what parts he had made I don't know if he'll speak with you but I'll ask. You can call me if you like, 631-871-6945.