I am using an A518 in my 70 Challenger.
I trimmed the case and made a rear mount of my own. A few pic are here in this thread.
https://board.moparts.org/ubbthread...4/re-four-speed-overdrive-automatic.htmlI am using the whole Magnum 5.9 EFI, Trans wiring, and ECU from a 95 Ram Truck. If you want to keep your Carb there are controllers that kick the overdrive in based on vacuum and a couple other factors.
Good info here.
https://board.moparts.org/ubbthreads/ubbthreads.php/topics/140864/re-727-to-a518-swap.htmlIf you are gong Big block and want to use an A518 then here is some info.
https://board.moparts.org/ubbthread...8-overdrive-conversion-lots-of-pics.htmlOtherwise Passon sells a 4 speed overdrive manual and there is always the gearvenders unit.
