V/8 Swap

Is it worth the money and effort to V/8 a A body mopar? I'm asking because I have seen some 6 cylinder cars that are in good shape, no rust.I did find a real clean 1974 duster for 29k. It's a 318 with ps, pdb, ac, is that a good price or outta sight? A classic car dealer in Illinois has a 1973 or 1974 duster that's in awesome condition but they are asking 41k and I don't think that it's worth that.