I'm using the 500R cdi box. everytime I switch the ignition power to ON, I get spark coming out of the 4 coils and sometimes a nasty backfire depending on what location the engine rotors are resting at.. any input would be appreciated..

 

ito try not leaving fuel in the motor this way it won't backfire.
so kill the fuel pump before you shut it off this way the motors dry.
Or try leaving the ign switch off and crank the motor over then turn on ign and should fire up without issues.

I've never had backfiring problems with all the cars i do. So i've never had to do anything about it. The cdi will spark all channels when first turned on.
The problem is you got to much unburnt fuel left in the motor.
this is common with haltech's...