Forget my answer, I read the Q wrong - thought you wanted to compare 3L SVT & 3L SHO. I agree with Brad, the SVT cams & Extrude Honing probably account for 15-18 of the 30 extra SVT horses on the 2.5L. So, multiply that by 6/5 for the 3L = about 20 HP.

1999 Amazon Green SVT Contour (#554/2760)
Stock SVT Duratec V6 with:
Intake- K&N filter/75mm MAF meter
Exhaust- MSDS Y-pipe/Bassani catback
Durability-Ford "dual mode" damper, Mobil 1/K&N oil filter
179.2 FWHP at 6900 RPM