I knew I shouldn't have posted this..
farr too technical for an old fart like me.
Right, I don't want to go too
radical with the bow shape, the pic that Dougal put up is about right...maybe a bit too much, but along those lines.
I was thinking of using a block of balsa epoxied into the bows (after cutting the existing piece out) and then sanding it to shape...a coat of resin over it to protect it should strengthen it sufficently.
A superstructure built up from thin styrene sheet, in a series of odd shaped boxes to give it that 'stealth' look, with the running gear consisting of two motors/shafts/rudders and a water pump based bow thruster. And that is basically it...I did have a go at one a few years back, based on a styrene yacht hull, but I built the superstructure far too heavy, and the finished product kept falling over, so it ended up being filed under B1N.