can ya hear the 440 run?
if so i would hear it run and make sure its a good motor. then i would yank it put a new chain,oil pump and water pump in and drop it in the dart after some cleaning and painting. i think you would be surprised at how good it will run.
headers are the biggest issue and are not cheap.
as far as the wp outlet goes there are a ton of different ways to go about it. my first big block abody swap i used the alumn mp housing. it came out on the drivers side and my rad outlet was on the pass side. i just got some exhaust pipe bent up to go from the wp around the oil filter and to the rad. worked great.