Yeah, welcome to the Forum. It would be best to run your half stack only and set the impedance on the amp to 8 ohms. This will be plenty loud. Trying to run a 16 and an 8 ohm load at the same time will not fly for long and I know you don't want to damage your amp. A 16 and an 8 ohm load in parallel is 5.33 ohms (just so you know).
Here is American Vikings thread:
Amp problems? Ohm questions? Amp blowing up for no reason, READ ME!
And here is Sticky's thread (very good):
SPEAKER WIRING