Took the tank off today. Turns out the top seal between petcock and tank got mangled on last reassembly. I noticed it had a slightly larger overall diameter due to swelling, but I thought I had it packed in there. Not. Thinking about trying the cork seat in the bottom. Buying a O-ring at the hardware store for the top seal. I keep hoping to get a little riding in before winter sets in.
Another thing, couldn't get the tank off w/out taking the petcock off first due to the hose barb hitting the tank bracket. While that's ok for getting the tank off, I'd like to have the petcock on correctly before putting the tank on. Just easier to see what I'm doing with the tank sitting in my lap. So I have three options. Cut a quarter inch off the hose barb. Cut a notch in the tank bracket. Or put the petcock on a third of a turn (probably) clockwise. That would put the valve in a less than ideal position, tho. Gonna have to kick it around a bit.