There are several ways. One of the simplist is to use the Pertronix set-up. I have one in mine and is works fine. It sure helped a lot. Other ways include the Mopar electronic conversion and an HEI conversion. Check out the Slant Six Forums for some additional insight.

1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)