If you can find a 4bbl intake, holley makes a TBI adapter that bolts on.
The rest of the fuel system is JY parts except the ECM.
If your not afraid of a bit of wiring( mainly removing wires...) then get a harness out of an 4.3 TBI astro van along with the rest of the fuel system.
Get an extra harness to use as a wire supply - some of the wires need to be extended.
The lowest cost for a ECM is to use megasquirt, but it does take some effort to read the manual and understand it. Otherwise buck up for something like a holley system. The trade off is with the holley you get a glossy manual in print and a tech number to call. With MS help is online via forums. I have a decent starting tuneup file for the MS that I made at the Texas convention 2 years ago.
