Assume it's end boom sheeting that is the problem with a bimini
. You can probably mount a traveler mid boom on the cabin
top to get the lines out of the way. Schaefer, Harkin, etc make kits to do this though you'll probably be into it for a boat unit by the time you are done. Might try Garhauer for the traveller. They tend to be cheaper than the big boys though don't know if they make the towers, etc to mount the traveller whey you want.
As far as the height of the boom, you may be able to recut the sail to raise the boom end. Consult with a sailmaker
to see if it's possible to do the recut. Failing that, they'll surely make you a new main to get the required height.