The guy that bought my 73 Duster had it swapped to a 4 speed, he bought the kit from brewers and had a resto shop do the work as it's way over his head, it ran about 8k to complete the swap but he also swapped a factory 4 speed column, new carpet,etc, it took the shop about 2 weeks to complete the swap- I sold him the car for 7k so I guess he really wanted a 4 speed.
My Dart is the other end of the spectrum, it took me a weekend and I have almost $0 invested- I bought almost everything used and flipped what I had 2 or 3 of. One example is I picked up 2 bells, 3 flywheels, a clutch fork, shifter and linkage of craigslist for $150- he threw in a 4 speed console too that he found while digging out the other parts- there were enough extra parts there to cover the cost of the trans, new clutch and some gaskets/seals from brewers.