Rob,
Vcc currently takes 6v from a car adapter. So it is more or less being run from the same supply as the arm and motor circuitry (consisting of two 12v 7AH sealed lead acid batteries in series -- 24v for the arm, 12v for the motor and a regulated 6v for the chip) This will change though...I'm going to try to use a battery pack with three C batteries (4.5v) and hope that the ouputs of the chips will still be high enough to turn on my first stage of transistors. If this doesn't work, I'll try a 7805 and use 4 C's.

I have decoupled each of the controllers with a .1uF ceramic cap. I honestly do not know the differences between different capacitor compositions, so if someone has the time I wouldn't mind being pointed in the direction of a good explanatory source...but that's a side topic for now.

Finally, I am using a simple RST config. I use a 10uF electrolytic conected from pin 9 to Vcc and a 10K resistor from 9 to ground.

From the sound of it, I think I'm just pumping too much voltage into these chips. That'll be my first circuit modification.

Thanks again everyone! Any other suggestions would certainately be appreciated.
Andy