Leave the heads, maybe do cams but if you are supercharging it you'll want blower cams... which will not be great while the car is NA.
I'd just swap it and get it on the road and then worry about upgrades.
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 ****.