Engine swap cobra 4.6

I'm restoring a 64.5 mustang and I found out that the engine is not the original 260. I found a 2001 4.6 svt cobra with T45 transmission for a good price and I'm doing the engine swap. :jaw: and heidit mustang II suspension.
I need more information on the wiring harness. Can I connect the 2001 harness to the original 64.5 mustang instrument panel? Or do I have to upgrade gauges? Does any 99 01 GT under dash harness work with the 2001cobra?
Please advice.
Thanks