Pure Magnum swap

I'm using my stock gauges, except for ammeter. I read in several forums about the problem with the alternator current going through the bulkhead connector and with the BIG splice under the dash. Even to the point of overheating and causing fire. I thought it would be a good opportunity to go ahead and rewire that situation. Plus, by using the PCM, all of that is fused. I still retained the original fuse panel under the dash for heater and wipers, dome light, instrument lights. Most of the lighting goes through the PCM now, utilizing the relays and separate fuses.
I'm not sure at this point on what to do with the water temp and oil press gauges. I think that the ECM uses those signals, especially the oil pressure.