If you're not using the PAB hole AND the mini Carling does arc, you can directly mount the bigger Carling switch in PAB hole. I have used it in both Tramps and both have been played maxed out w/ no signs of arcing. Mouser 691-2GL50-73 for $7.22 USD. Don't know what the shipping would be though. Would still like to see gut shot of amp

And you'll like the EL34 power tube (well, I do and I'm not a player, but just banging around w/ a test guitar and hearing real players using the amp, it seems smoother than the 6L6). PS Didn't heat shrink or otherwise insulate the lugs on the big switch and no arcing at max loads.