I have an '81 firebird w/a buick 231 v6 th350c combo. I am looking for advice on the most economical v8 swap in both dollars and the amount of work involved. The most likely candidates seem to be sbc( requires a tranny swap possibly),400 pontiac, or 403 olds. I realize there will be a bunch of people who will say a pontiac should have a pontiac motor. I am looking for more drivability from it. The car is currently parked in Colorado where it has been sitting for most of the last 15 years. I live in Tacoma, WA. Getting the car here may also be problematic, I may have to have it shipped out here as previous driving experience with it tells me not to trust driving it here. I've no immediate plans but will eventually have to do something with it. It can't stay where it is forever. I appreciate the advise or opinions i will get.  

Bat, first off, my suggestion for getting the car home is only a guess, because I've no idea how far you are taking about. There are a few ways to deal with this, if the car currently runs and is safe for the road, you might want to take it to a reputable shop and have it tuned up and checked over so you can drive it home with no problems. If this is not possible, what about renting a pickup truck or fullsize van with a trailer hitch and a car dolly and towing it home yourself? One item to consider is that the front wheels of the car must be safe, because they will be on the road all the time- so repack wheel bearings and make sure the tires are safe! Or just go the whole hog and rent a car trailer to tow it home. Another option is having it shipped on a car hauler, usually the car must be driveable enough to drive onto the trailer. Do an internet search or Yellow pages search to find a shipper or call moving companies such as North American, Allied or Mayflower van lines (don't even know if any of them are still around, but you get the idea), they will be able to put you in touch with someone.
As for the actual engine swap, your best bet, regardless of which engine you choose, is to find a mid-70's to 81 Firebird or TA or Camaro (if you decide on Chevy power) that you can buy cheap with the drivetrain you want and swap everything you need. All of the engine swaps you listed require new frame and block mounts, only the SBC requires a different trans (unless your th350 has a dual bolt pattern), all will require new exhaust, preferably duals and there may be issues requiring the wire harness and battery to be rerouted as well as fuel lines. The Pontiac v8 has the starter, alternator, fuel pump/line and battery on the driver's side. The SBC has them all on the right side. The Olds 403, I believe has everything on the right as well. Each engine family has it's strong points: the SBC of course is the cheapest and easiest to get parts and info, it's also the lightest and most compact, the Pontiac and Olds are about the same size/weight but the Pontiac generally has a longer stroke, making more torque and it is of course "pure Pontiac"! Any other questions, just ask!
Steve  

after checking into the cost of shipping it 1500+ miles($1000 or more non-drivable), towing is not a viable option either, I'm think my best option might be to just have someone sell it for me and buy a local v8 car(driver), don't have adequite room for a parts car and a project car. I would like to go with the current car just because I already own it(traded a ranchero for it 18 years ago), but I'm not married to it. Thanks for the advice, appreciate it.