Holley markets a throttle-body injection system called Pro-Jection. It's pretty pricey, and performs best at full throttle. I'd be prone to think it would be simpler to grab a GM wiring diagram, and work on adapting a throttle body injection system from a 2.8 or a 4.3 Liter V-6 to a stovebolt engine. A few sensors and some wiring, and it wouldn't be too difficult to set up. The HEI distributor from the V-6 would need to be adapted to the inline engine to trigger the injection pulses for the computer.

Edit: Here's a tech article on installing a ProJection unit on a Jeep I-6, and it seems they're pretty pleased with it.

http://www.4x4review.com/products/electrical/holley-projection.asp

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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