there's something wrong in your calculations:
.496/134.451 is the number of CuCl2 moles, right? why do u divide it by 2? there are 3 CuCl2 moles, not 2.
i dont think u can find the theoretical mass and moles of total Al, only the mass and moles that react with CuCl. thats because Al is in excess.
"I guess I'm just not sure if you can find the theoretical moles of AlCl3 and then just multiply it by the molar mass of Al and have that work out."
that will work!, its the same as your above equation, except that u did the wrong thing in finding out 2 moles. only u'll find the mass of Al that reacts with the CuCl and not that excess total, of course.