If you happen to live in a seasonally Arctic where the powers that be see it fit to scatter corrosives on the road (i.e. f*ckin' salt) then here are a few particulars that may save you some time and dissapointment down the road...
1. salt makes all the steel fasteners weld themselves the alluminum case quite snugly... now they naturaly will do this anyway, as there is a chemical reaction between the two types of metal, alluminum alloy and steel; therefore impact tools of any variety will come to be the centerpiece of your alter.
2. any fastener with a Phillip's head replace with hardened steel or titanium alloy...(hey, there aren't that many bolts holding the throw-rod bearing shit on the bike...)...with steel fasteners it is wise to allways coat the threads lightly with an alluminum oxide 'anti-sieze' to ensure not ever snapping off another fastener in the case and hours spent picking out threads with dentistry tools, drooling on yourself because you have a small mag-light clenched in your teeth to illuminate that impossibly deep, dark, shaft...
side note: wrap the last inch of the mag-light down to the seam where the end screws on in a healthy dose of electricians tape to give yourself a bit of padding while clenching said flashlight in mouth, on the shoulder of a seldom used highway, in a torrential downpour; essentialy giving you an extra hand to sort out your little ignition problem.