I have been collecting info in the links here for my eventual ls swap. I wrote this years ago. Some info is no longer accurate.
viewtopic.php?f=1&t=33358I don't believe an ls swap could be done cleanly for less than $3000 (probably more) and that would be with a 5.3 or 4.8 used engine, used parts as much as possible, as many ebay deals as can be had, carbureted, etc.
you need an engine, mounts, intake, pan, kit to modify pan, oil pickup, welding, manifolds, exhaust mods, water pump, brackets, accessories, electric fan, bellhousing, flywheel, fabrication, possible steering shaft mods, lots of misc. stuff. If you go injected then the costs go up - you need a harness. If you go dbw the cost go up again. If you go injected and your engine is not stock then add tuning costs.
You could add ls electronics to you sbc using parts by eficonnection
https://www.eficonnection.com/home/cate ... fi-24x-sbc