I finally got my tank mounted Stein. RVator pulled the tank from his US 60 and it's a 12oz so we stuck it in and it works fine. My mount holds it very tight and makes removal a snap. I'm currently fighting the cowl and trying to get it cut for the engine and pipe. I think I'm gonna just use the muffler pipe and clamp a rubber extension on it and not even use the muffler at all. Later if it's too loud I'll rig up the muffler some way. I'm sick of working on this thing and want to get it in the air. If it doesn't suit me, it will be for sell real quick.
BTW, I used a rotobroach to cut the holes in the belly pan (it's glued to the wing) and man what a job that thing does. Perfect round holes and no clean up at all. I'll use it to cut holes for the fuel dots too. Do you have any photos of how your cowl is mounted? How much of the bottom did you remove? How many and what size screws do you use? I have #6 Button head and bonded washers. Did you beef up the fuse to hold the cowl?