Car-topable hulls for HC16 rig?

[Blacky]

hello,
I would like to take a beachcat with us on holiday. We cant tow a trailer because we already tow a caravan. So I have to transport the cat on top of the car. Transporting on top of the caravan is not possible.
A HC16 is here, but its too heavy and too long.
Dont wanna buy or build a complete second cat. Instead I would like to use
rig and (main) sail of the HC16.

Therefore I am looking for a beachcat design for self-building:
- not longer than 15' / 4.8m
- hulls + beams not heaghier than 65kg
- which can be used with hobie 16 rig & sails and rudders
- able to carry two person

Any idea which cat design I could build?
thx!
Blacky