Hi Terry,
A little more information for you.
The sensor that I am replacing (you'll need to order) are the fuel pressure, oil pressure and oil temp.
I also ordered the the three wiring harnesses. After removing the shrink tubing for one of the CHT probes, I decided that it would be easier to build the probe harness out of my existing wires.
The problem is that after almost 4 years of flying the shrink tube has fused into a solid block of plastic and it takes a long time to carefully trim away the plastic. If you have enough length in your existing probe wires than hooking the ends to a D-25 connector will be easier that using AFS harness.
The other two harness (other instruments and communication) will be evaluated which way will be easier.
Kent