All the mc28's electronic restriction is in the card.
An 030 card with either a wirespliced or HRC loom sets the timing as HRC wanted it for that card. There's nothing else to do, you can't chop wires around and alter things. That's why there were 4 commercially available cards and several others not sold to the public at all.

If its a track bike and you stick with the PGM-IV you may as well get the HRC loom, they aren't massive money. That makes the kill switch a power switch and lets you leave the card properly in it's slot all the time, not pulled half out to turn the ignition off.

If you go to the PGM-III you could get an HRC loom and derestrctor box though they are quite a lot of money. Make sure you get both bits!
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