Sounds like you've got a solid handle on the process. But, if I understand you correctly, you tapped the high pressure cutoff into clutch power? It wants to be in series, so clutch power cut and each leg of the switch pigtail attached to one side of the wire.
Stock, clutch power goes through the low pressure switch, then high pressure switch, then WOT relay. The exact order of the 3 components shouldn't matter, but you do want them all to be before the diode, so make sure you're not grabbing the wire between the diode and the clutch.
