Hey James,
I'm no expert either, but, I would consider the helicoil if you can find the right size and length. A lot of aluminum parts which have a high load/tension come with helicoils as the helicoil is a harder metal than the aluminum itself. The only issue is having enough metal around the helicoil itself so you don's lose the integrity of the part. I would also mount the part up in a drill press fixture and use a pilot to make sure the hole is centered and the hole is drilled straight. You can also use the drill head to guide the tap, BY HAND ONLY... do not turn on the drill press on to tap the threads... once again, you use it only as a guide and turn it by hand. Turn it in 1/4-1/2 (when it gets snug) a turn and reverse rotation to break the chip... use plenty of tap oil as well. Good Luck!