Actually, moving the ship out of the way is Sarah's job.  :-)  Getting engineering clear is a matter of not having the heretics figure out how to trigger the self destruct mechanism without a code from the bridge.<br/><br/>As for disabling a torpedo with a shuttle, the most plausable way of doing so is most likely to pilot a course directly into the path of the torpedo, have a person in a void suit jump onto the surface of the torpedo using a magnetic clamp, then saw through the hull of the torpedo and sabotage the plasma reactor.  Likely doable for space marines, but a seriously epic endeavor for anyone else.<br/><br/>Torpedo armor is really really strong on the front, kitten weak on the back, except that it moves faster than pretty much anything that can pursue it other than a full starship.  (In the warhammer 40k setting, it's easier to get something with a full scale plasma reactor moving really fast than it is something small)<br/><br/>You do have the opportunity to intercept torpedoes with the turret defenses of the Kobras Aquairre, which might take out 1-2 torpedoes, so eliminating two torpedoes might just be enough.