Absolutely, I purchased a set of windsor jrs and took them to a machine shop to have them disassembled. Spent a few hours a night for about 2 weeks off and on cleaning up the bowls and smoothing the exhaust ports. Compared to the last set of untouched box stock windsor jr heads I had these were a nice improvement. Be prepared to spend a little for the sanding rolls and the right tools. I used both air and electric die grinders.