Has anyone changed an early (pre-87) truck from carburetor to throttle body? If so, I assume you need the computer and harness, the throttle body system and an elect. fuel pump. What else?. Would it be worth the trouble, if I could find a good used set-up? I have had a few 87 models that ran good and got decent mileage. My truck's gas mileage is starting to wear on me. Thanks, Randy