I didn't like the idea of cutting the frame, but now that I did it, it was a good decision. I did not want to do any welding because it seemed risky and expensive, so I used JB Weld to attach bungs to the frame ends. To make the bungs fit snuggly, I inserted small sections of 7/8" tubing from an old set of handlebars that I had in the shop and used JB Weld around these too. You must clean the metal surfaces with a steel brush to get everything properly prepared for the epoxy. In certain situations, JB Weld can be used and it is very, very strong when used correctly. I believe this is one of those uses where it can be used instead of welding. I also threaded a screw into the bung to make it even stronger, but this is probably overkill.
Before you cut anything, screw in two small 1/4" steel/aluminum sections underneath the thin vertical wings that attach the lower bars to the top bar. This way, you can ensure the cut section will be remounted as it was before you made the cut. I inserted the section into place and took a few pictures so you can see what it looks like. I did not screw it into place because I am still working on the engine. Trust me, this is as strong as it was before the cut.