I don't think remote starters work on carburated cars with a manual trans.
I have to warm it like they did in the 70s
The only thing I wish was different about a 68 dart and cars like it, is if they would have had better vents. I like dash vents and vents that point heat to your face and feet like in new cars but my 68 has the single vent in the middle on the transmission tunnel....... leaves a lot to be desired