I just did this two weeks ago on a DC-3 wing tip:
viewtopic.php?f=26&t=56964Definitely borrow a generator for the job as electric tools are ideal for the job (don't forget the extensions cords). As mentioned by ALOHADAVE, a recip saw with plenty of replacement blades is good but also an angle grinder with a metal cutting blade will make short work of the task. It cuts through the aluminum like a hot knife going through butter! A couple of replacement blade wheels would also be a good idea. If you haven't used one before be very careful with an angle grinder though. They spin at over 1000 rpm so if a blade lets go it will throw the bits everywhere at high speed which is why they come with a protective guard. Also, don't place it down until it stops spinning. Learn how to use it safely and then go have some fun!