I just bought a Holley Fuel pump #12-920 for my EFI conversion in my '66 Mustang. Here's the specs, and the car is running. I don't have a pressure gauge to measure the PSI though. Make sure you have a low pressure filter before the fuel pump (get one for a carb'd engine) and then the high pressure filter after your pump (i used the stock 91 mustang fuel filter).
From what I understand the throttle body applications are at 15PSI, and our multi-port ones are 45PSI (for my fuel pump). I don't know how it can tell the difference, but it seems to work just fine. You have to make sure you get a high pressure pump - I called all auto parts places (advance, O'rielley, autozone, napa) and they didn't have any. I went to my alamo performance dealer in San Antonio and purchased the pump. Although I probably would have just got one online if I weren't pressed for time.
Specifications for 510-12-920:
# Can be used with throttle body or multi-point injection
# Can be used on forced induction applications
# 80 GPH flow @ 15 PSI (at 13.5 volts)
# 480 PPH flow @ 15 PSI (at 13.5 volts)
# 5 amp current draw @ 15 PSI
# 67 GPH flow @ 45 PSI (at 13.5 volts)
# 402 PPH @ 45 PSI (at 13.5 volts)
# 8 amp current draw @ 45 PSI
# Supports throttle body injection up to 800 HP
# Supports multi-point injection up to 700 HP naturally aspirated
# Supports forced induction, multi-point injection up to 600 HP
