As long as you're doing the wires it wouldn't be a bad idea to remove the plug cap internals and inspect for corrosion....go in the spark plug end with a slotted screwdriver to remove the plug holder, resistor, brass disc and spring.
This is what you'll find (they are MaximX but same as VMax).... http://www.maxim-x.com/pix/plugcaps/1-maximx_plugcap_and_parts.jpg
This is what you'll find (they are MaximX but same as VMax).... http://www.maxim-x.com/pix/plugcaps/1-maximx_plugcap_and_parts.jpg