Also keep in mind that although it very fluffily talks about using hard-mounted weaponry (if you really WANTED to use the hull lasguns, that is) it is still the embarked squad firing, not the chimera, and so are subject to the vehicle movement rules on
pg.66
On a related note, I'm going to model my next chimera with Lascannons flanking the hatch. For reality's sake, of course.
DoW