This is probably the one you are looking for.
http://www.thundermustang.com/
Have the volume up when you open the web page, they have a recording of the Falconer V12 at full song!
Performance wise it smokes the original below 15,000' or so (composite = lighter (no guns etc) and improved naca airfoil & smaller wing required due less weight), no blower so up higher it suffers. Although they were looking at putting a blower on it and some have been re-engined with turbine power.
Generally one of the faster normally aspirated aircraft at Reno (see
www.bluethunderairracing.com )
Now if I could only find a buyer for the kids
PERFORMANCE Thunder Mustang {P51}
Rate of Climb @ gross 5200 ft/min {P51 2800 ft/min}
Maximum Level Speed @ Sea Level 326 kts (375 mph) {P51 326 kts (375 mph) 380 kts (437mph @ 25000ft.)}
Cruise Speed @ 75% Power 300kts (340 mph) 22-25 gph {P51 250 kts (300 mph) 50-75gph}
Range 1300 naut. mi. {P51 700 naut. mi. }
Service Ceiling 25,000 ft. {P 5146,000 ft. }