http://www.vintageperformance.com/retro ... evrole.htm
here are the El conversion for the Luv truck.
I have 3 of these myself (2 510s&521pick up) and also done a Jeep and old Corvette.
These are great units and looks stock with 2 wire hook up. It uses the stock ballast and coil(Do not use full 12v coils).
You can find them cheaper than 70$ sometimes.
Here is also a great weber site that is the cheapest I could find.
Even has the weber w/ the IC solinoid cutt off for the idle jet(if you have RUN ON proplems).
http://www.webercarbsdirect.com/chevrolet