RE: need help with sundowner 50
I've just put my OS 91 Surpass 4st in mine - fitted fine, just small clearance hole for the fins on top of the cheek, and below for the exhaust header. Had to plug and redrill the mounts 3mm wider each side. Muffler inside cowl - easy.
I've yet to finish and balance it, but will put the battery behind the servos if need be - will open up the covering underneath to gain access if this transpires, easy to match the white underside.
Planning on trying 13x7, 13x8, 12x8 initially.
Cam