I built a car that I'd order, a 1SS with the brembos, adaptive suspension, and sports exhaust, and it was 7500 more MSRP than my Mustang. $43,500 vs 35,900.
If you remove the suspension and exhaust that aren't available on Mustang, it's still $5,000 more.
I bet the ZL1 will base in the 60s and option over 70.