Not hard at all, I just done this for a friend on a 91 Dodge pickup, First you need to get a good fuel pressure regulator, EFI run's off [throttle body type] 18 psi, injector type run's off 45 psi, remove intake and throttle body, install new intake and carb, run line from regulator to carb set fuel pressure to 7 psi, fire engine and start driving, throttle cable same from one to other.