Vincent's are great things to have. had the same in NZ at Christchurch, but I had assistance from Russle Byfield that I spent three days with him and the two guys that ran a bike shop, swapped the steel brake drums around as bolt holes were slotted. Alan bolts were fitted (into new holes) from inside to out as radius of steed pressed drums hexagon bolts didn't fit squarely enough, spring washer and nylocks and it just clears the brake torque arms. Harvey shipped the bikes home after he toured NZ in 2019 since then the rear wheel has been put on the "A" Comet and a new wheel built for the twin with WM4 x 21"!!? the same as the front with SPEET T.L.S.brakes.