71 DEMON - slant6/3 speed manual to RB/727 - Questions!

IIRC,tranny mount should work/727 will fit/pedal can be removed, no prob/I believe the pan should work-it should be a center sump pan, I believe the chrysler C had the center sump pan- if not get one for a B Body, 69 vintage 383/ I would stick with the Schumacher's motor mounts, they are proven and the design has been been upgraded to make them stronger. Yeah I know they are more $ but.....
Only thing you may not like about removing the clutch pedal is the placement of the brake pedal itself....It would be better if you could find an actual auto equipped pedal.
Should not be hard to find.