why don’t you just raise it  a few inches …if you can build up the transom  it should fit     see  my 50hp merc years ago      great rig!!

I installed  2 x 3/4 marine plymood plates to replace the original  (low) transom wood  and one angle  iron on top on which the Merc sat.

Built a console  to sit on the middle seat  with cables extended one one side back to the Merc.

it will be factory  just sitting higher up   a bit 🙂