Very easy to do...
Use the 4 sets of wires that come off the balast, use 1 color for each end of the bulb.
(2 red go in one end, 2 blue in the other,etc..)
I have 2 balasts on my 90, running 440 on one and 220 on the other.
let me know if you need any other help.
Jedi
