Valiant to Duster disc brake/rear brake swap

I dont know if anyone makes adapter mounts to put a slant 6 on a V8 K. I would leave the Duster as is and drive it while I pull the 318 and rebuild it, the trans, and the suspension as if the Valiant was going to be my next driver. Once its all done, running and driving like a new one, all of it can be moved to the Duster in a weekend. After a few weeks of enjoying the Duster you could poke all you pulled under the Valiant so its at least a roller again.
It will be easier to forfeit the power steering. Keep manual steering gear and that column. Use the Valiants proportion valve, fluid lines and all. Buy a manual brake master cylinder for a 73 Valiant with front discs. Push rod from Duster might transfer too. I personally would want the power steering and power brakes but its not my Duster.