To etch the aluminum, use a product like Jasco Metal-Prep. It's dilute phosphoric acid solution with surfactants, available at Home Depot, Lowes, or probably paint supply shops. If your A&P uses Alodine, he probably has Alumi-Prep as well, which is used first to etch the aluminum. Pretty much the same stuff as Jasco, only more expensive. Either will work.

Probably the best adhesive for this is Loctite 330 Depend. Unlike most epoxies that get hard, 330 retains some elasticity which allows it to work well bonding materials with dissimilar thermal coefficients of expansion (without the need holes or FRP overlays etc). 330 is a fast bonding two part acrylic adhesive that bonds most anything to most anything with few exceptions. You apply the gel to one part, spray the activator on the other, and hold the parts together for a few minutes. No need for clamping and fixtures in most cases. Full strength in 24 hours and as I recall, a strength of 2,000 psi in shear.

It's available on Amazon etc. not cheap, but works wonders. Bad news is shelf life is one year, and they are serious about that - I think on day 366 it stops working, so don't buy a lot more than you'll need.