You can use a "red monster" harness. It is plug and play. Available on multiple mustang forums, the corral has listings for them and SVTP I think. Just google "red monster corral" and see what you get. Your other option is to re-use the coil packs from the 97 and don't even worry about it. OEM plug wires are way cheaper than new COPS and the 97 computer will run the PI motor just fine with no tuning required.
2000 Mustang GT Steeda #0048 34k miles. 99 Cobra 4V swapped, FTBR IRS swapped, exhaust, tuned by James Gordon.
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.