Go with the flat pack so you can put it way up front, then if you need to you will also be able to put your rec. a little farther forward. Then if it still isn't enough move the engine out a bit. You will be surprised that just moving the engine a little will make a lot of difference. What ever you do TRY to not add any more weight. That said if all else fails buy a heavy prop nut. The 40la is no power house but if you keep the weight down it should do OK. ENJOY !!! RED