Curious, did they supply a mounting template?
Do you have a cherry picker? Works great to lift and install the bracket. You can make a template which is what I did but I found it much easier on brother's build to use the bracket itself as the template. Mark the center line on the transom and a horizontal line at the appropriate mounting height depending on the shaft size of your motor, then use the cherry picker to get the bracket in place. Drill the two outer holes on each side of the bracket and install those two bolts and snug them up, then with a sharpie mark all the remaining mounting holes. Question, why is there four upper mounting holes for the motor and no Armstrong logo?