If you go to the bottom of the home page for this site and click on the Tips & Tricks link, then click on the Early Hemi to B&E Body Engine Swap article, then click the link to the PDF file you can read my article on that swap. You can also check out the other article by Mopar Charlie, which has some good info, but also has some misleading info too. The biggest hassle to the swap is the problem of headers if you don't want to run factory exhaust manifolds, there aren't any off the shelf that will fit and you will have to modify some as described in my article. Otherwise it's not too hard of a swap, but to be brutally honest with you, you can probably get more power out of a well built B or RB engine and carry 100 lbs less weight over the front suspension. All things being equal, the rebuilt 392 is worth more than a rebuilt 383, and if you're more interested in seeing a big set of hemi valve covers under your hood than in how much horsepower you can put to the ground then I would say go for it!
Owner of the Poor Man's Hemi Cuda