You won't need much.
In addition to the V8 long block and transmission, you'll need everything else that goes on the engine ( intake, carb, air cleaner, covers/pan, distributor with related ignition parts, exhaust manifolds or headers, starter, flywheel, torque converter, alternator, fuel pump and lines, various engine brackets and pullies, etc. ), engine block mounts, V8 frame mounts, V8 throttle linkage, V8 radiator with related hoses, transmission cooler lines, TH350 style shifter linkage conversion parts or kit, V8 front springs, a new dual exhuast system, and probably a bunch of small various nickle and dime parts that I can't think of right now.
In other words, the conversion is easy. It just costs more money than you might anticipate not to mention you car will be "down" for a long period.
You might want to think about keeping the L6 and working on it. They can be made to make decent power plus they make your car stand out in a sea of typical V8s. Not to mention it would probably be cheaper to fix what you have. Also being able to drive the car as you work on it is a lot more fun than it sitting in the garrage for months or years. But if you have all the parts gathered and engine/trans fully assembled and ready to drop in, then the job can be done in a few days.
it sounded like a rod went out on my fantastic straight 6, so i haven't even bothered looking at it.
the 350 v8 i want to drop in is from a 71 el camino, was running great off a recent rebuild when it came out. but now that i think about all the associated costs, plus towing to huntington beach, i can probably fix the L6 much faster and cheaper...? need some advice
the L6 is the original 40 year old brick of a motor, never been rebuilt and one day i went to start it and it screeched, died. engine seems to be siezed- crestfallen i started looking at new motors as i had anticipated doing in about a month. hoped to get a few more miles out of her before upgrading, much less to at least drive to work until i had saved up a couple thousand to throw at it. but now i bike to work and need to get this fixed up asap. my buddy in huntington has the complete 350 set up out of his el camino. i figured that would be the way to go and is way cheaper than going from manufacturer or shop for a rebuilt 350. he will even help me install, so i'm interested.
but if there's something i can do with L6 to get her back runnin on a dime let me know. i'm pretty sure a rod went out
The only way to know for sure if the L6 is salvageable is to pull it out ( you gonna have to anyway ) and remove the oil pan to get a look inside. Usually a thrown rod is accompanied by a hole in the block or pan. Sometimes a big outward dent in the pan is an indicator of a thrown rod. If the crank won't turn over, then somthing is wrong for sure. If that is the case, your easiest least expensive fix would be to locate another useable L6 shortblock ( with gasket kit ) and reuse your cylinder head (longblock if your cylinder head is damaged), pan, covers manifolds, etc. drop it back in and go. A used shortblock should be easy to find in any pullapart salvage yard ( with optional warranty) or private sellers who practically give these engines away. You're more likely to find a 250 ( same cylinder bore, just longer stroke )rather than a 230, but all the parts will swap over if that is the case. Watch out for the 194 (smaller cylinder bore and small chamber head )or 292 ( different block dimensions ) as they do have some differences.
You might just be able to get by with a crank kit and possibly a replacement new or used 230 or 194 connecting rod.
But if you've always planned for a V8 anyway, now might be the time to do it.