I checked my stored gear and all I could find that might help was a few Semco adapters that look like 60 size and two straps designed for their mufflers. The only muffler I had left was for a 40 size helicopter engine which has the port 90 degrees to the muffler body. No help there. So, if you can find a 60 size Semco strap on muffler, one of the two adapters I have might fit. Best I can do. I'd put in a 'wanted' ad on RCU. There have to be a lot of guys with old Semcos hanging around. From the 1970s. Ouch, I'm getting really old.