Trust me, I learned back when I got layed off that 3WW wasn't gonna contribute to my income very much. Be my guest to buy propane tanks, empty them and do that work to get them cut and square.
BTW, I tried 3 250R air-boxes, ALL were about 1MM smaller in the center, I guess from tightening and loosening the clamps........ I'd make a sleeve and it would be tight in the center but not so great on the boot and AF; Then again, I'm fussy and I like aluminum......
I found 2 slightly larger rings to fit better but no one will cough up the cash or I'd be making them. If I get firm requests, I'll make them.....
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country