Is this a duelly truck by chance :?: I wouldn't touch it if it is, i can guarentee you that the Edelbrock EFI, will not be worth the $2,000.00 over the throttle body. If it's conventual truck, not a duelly, you'd be better off to change the heads, and up the cam a little and stay with the throttle body. I've got a 1993 duelly with 189,000 miles on it and it pulls a 28 ft Haulmark with an over 3,000 lb car all day as fast as the speed limit allows, and will still spin the tires with no load on it, i wouldn't touch it for nothing. It's never had any engine work done too it, but i'm a little surprised that the plastic timing gear hasn't gone out yet.
JMO
Zip.