stage 1 roush

I have a 1999 Roush Stage 1 V6 Mustang 5 speed and have recently acquired a 97 Mark Viii. I have access to everything in the Mark VII and know most of what the swap needs. My Main question is what work would need be done to wire my gauges and such into the Mark Viii ECU or if its even possible.

Hey I'm buying my first car and I caught a ride around base today in a guys 06 roush stage 1. I thought it was amazing so I asked him if he ever thought about selling it. He said he would take 12000 with 89000 miles on it but isn't actively trying to sell. just wondering if it was a good price...