So you want 2 go Big block...Read this first!

I only read the first two, then the last page...lol. Careful, it's starting to sound like moparts over here :D.

I've done a few swaps first hand. Then run the gambit from making me $150 on a bet to over $10gs for a small block. So lets establish a guideline or two.
You need a car that has 10' paint job, runs and drives on the street, mimickign a stock car. I think by adding those three limits, we can compare apples to apples. Now, my bet car.. I got a '72 Swinger /6 with a hole in the block, and a '67 sport fury, both for free, and I was told no way could I get the 383 into the dart buying nothing but tuneup stuff, a rear end case and axles, and exhaust. I won. 383 2bbl, column shift 727, and one legger 8 3/4. I had the 8 3/4 case. Everything else was fabbed by using my head and parts from either car. I did need the 2bbl exh log angle milled, which was a favor for me by a friend. But I think adding the banjo and the milling at todays prices, I could do it for $300. Fully done and driving. It's now been totally redone with a mean 451 in it. I'm happy it was rescued from the recycler.
For a big block to be functional and safe (by original manufacturer specs for that year) you don't need disk brakes. Most guys love them, but many guys now-a-days never had a drum brake car of anythign with a choke ever in thier life. Before the insurance push of the early 70s stopping in time and reasonable speed was the responsibility of the driver... not the manufacturer. So my pricing would go like this:
RB wedge from /6 car:
engine (running stock 440) - $1000
trans (stock rebuild done by local shop, w/stock convertor) - $800
rear axle (working 8 3/4 comp w/SBP axles and 3.23 gear one legger) - $500
Exh manifolds (someone makes HP manifolds modified for A body) - $300
Exh system - $1000 (I use custom bent stuff, 2.5", with good mufflers and tips)
Misc stuff (subframe connectors, kickdown cable, hoses, belts, tune up, carb kit, paint, gasket set, driveshaft, centerlink, tie rods, oil pan, various safety items like brakes and brake hoses/lines, tires, etc. - $2000.

total - 5600, and we havent gotten the car yet. I am thinking of doing a similar project in the near future should some things in my life get finished. I'll track every cent and see what it costs... The best car to get if you're going to big block one is a running car. V-8 preferred. And early V8 should have an 8 3/4 and decent radiator. A later water pump housing and timing cover can be run with a little tweaking to utilize the outlet configuration on the small V8. You dont need a 4 row aluminum.. it's en-vogue, but not necessary. You do need a fan shroud, a decent fan or fans, and an engine in general good state of shape. You don't need headers or 3" pipe. Those that say it's a must have weren't driving the cars with 2 1/4 pipes with Sonic Turbos and still running well. You don't need a dana 60 unless you are making mad power AND can hook it up. That 383 2bbl could do a 2-3 gear one legger holeshot for over 100yds from a dead stop. I've priced two complete cars in the past two years, starting from a fairly rust free running V8 car, and ending with a mid 10s capable street car, with me doing all the work (including cage/suspension and body/paint) They come to between 20K and 25K. Once you reach a certain performance window (about low 12s) the pricing gets almost the same for big or small block. You end up needing the same things.