Motorized Surfski - How?

After researching many possible design ideas I've come to the conclusion that a surfski suits my needs better than most other options, however, I need to figure out where/how best to mount a small inboard or outboard motor to it. Assuming I use outriggers of some-kind for stability where do you think the motor should go - behind the back of the person closest to the stern (through a cutout in the hull); between the two people on board; mounted to a bracket built up from the stern; mounted to a bracket built up from a squared off stern (cut between the back driver and original stern), mounted to the side of the hull on one of the outrigger arms, etc? The motors I had planned on using weigh in at about 50lbs (the inboard is maybe 5-10lbs lighter) and rate in at 6hp. Mounting it directly off the stern seems easiest but the prop will undoubtedly come out of the water when we go over the crest of a wave (and the extra weight of the motor this far towards the back might throw off the good dynamics the hulls inherently have) - hence my thinking that the motor needs to be as close to the centre of the length of the hull as possible. Another easy option seems to be simply mounting the outboard to the bracket of one of the outriggers but I wasn't sure how efficient the hull would be with propulsion coming roughly 15-20" outside of the centre line - would this make much difference at the small horsepower I'll be using? The inboard option looks to be the hardest and would require cutting a hole in the surfski hull but might work best due to it's lighter weight, closeness to the centre of the hull, and lower centre of gravity.

Please share any thoughts/ideas on this - I really need some expert advice...
Thanks in advance.

 

To much horsepowr? Perhaps half that is to much.

No hole in hull. put it outside

 

Something like this may help-they seem to have a very small flat engine:
http://www.powerski.com/content/psi_index.php

video: http://www.youtube.com/watch?v=rOE_0HBIGFk

Interesting site: http://www.huki.com/

click on image:

 

http://www.marinetrader.com.au/boat/405865/fibreglass_-power_board_moulds_-power_board_extreme/

like this?