Easiest way Ive seen is to put the zilla motor in with the swinger bolt, then you'll see where the frame rail needs to be notched for the lower mount. with that done it will drop in place, put the thru bolt in and then the SBLT front motor mounts. Then you'll see where the cut out for spark plug access and for the kicker to rotate need to be also the flat bracket w/2 holes on the front down tube needs to be notched for the pipe. I would also recommend some gussets.