Magnum 318
I've done this into a '68 Dart with a 5.9 Magnum and a 4 speed.
As far as bolting in, if you use a 904, 727, or 4 speed, it's pretty simple and basic.
You will need a '71-'81 360 CAR oil pan to install it, a pre-'92 318 pan will NOT work!
5 speeds, 518 (46r or 46re) or 500s require extensive floor and transmission mount modifications, which negate a trouble-free installation.
The wiring for the EFI is a trial in patience and time consuming, requiring untaping, eliminating certain systems not related to fuel, ignition or emissions and re-taping it.
I used the stock Magnum fuel pump, which was attached to a slightly modified stock '68 Dart sending unit.
Mark.