42RH SWAP

I have a 68 Dart with a 408 and a 727 trans. Looking between the GV and a 42 RH swap. I'm in Canada so at 35 cents on the dollar the GV gets real expensive. I have a 42RH out of a 90 v6 Dakota. I dont need a lockup convertor so I'm curious if the 42RH can be modified to accept a regular 904 convertor? (Higher stall).I'm aware of the fitment and chassis mods required.
Thanks