How many using an A500 overdrive ?

This may have been answered before but I currently have a stock 318 with a 904 trans. I want to get an overdrive unit but I’m not very knowledgeable on transmission options. I found this on eBay Dodge 2wd Overdrive Unit REBUILT 46RE 47RE 42RE A500 A518 Transmission | eBay

My question is: would this work for me? Would this be a bolt on and go. I know I would need to modify the mount and driveshaft but other than that is it what I’m looking for?