Mast location Cross 38

[Red Horse]

Hi all ,
My boat was rigged as a ketch, the mizzen was used infrequently and always in the way. So now the boat is sans mizzen.
I have drawings from John Marples to change to a cutter rig. This requires moving the mast location about 4 feet aft. And 6 feet taller. I would have to install a compression post. Which would impact the visuals of the interior. The rig would be taller and would have a longer boom. The drawings also call for a double set of diamonds. This would help with the main up against the lower after stays on a reach.
The boat sails ok as presently rigged. Although the boom is about 3 feet shorter than required for even the ketch rig.
So just wondering if anyone one the on the forum has a cutter rig or the sloop rig and could maybe give me some input. I have tried searching the web and found a few boats but all appear to have the mast on the fwd cross beam with a boom extending to the aft end of the cockpit.

Thanks
sarge