Take a Skilsaw! A Milwaukee metal cutting saw 'might' be better, but a friend of mine, who built about a thousand Herring skiffs, swore by his basic Skilsaw and whatever saw blades were cheapest at the counter of the Hardware store! And, he was a big fan of hearing protection! Just sayin'!
FWIW, if you chuck it in the truck bed and run, a wood cutting band saw works a treat on Aluminum. Bugger the whole 'two or three teeth always in contact! Run the wood saw as fast as it can go, and simply enough, don't act like you are simple, feeding the aluminum in to the blade! Ie: be gentIe! I have cut up to 4 inch thick plate on my crappy salvaged wood band saw! Feed according to how much it slows down, and it will all be a happy solution! Remarkably little heat generated!