Does anyone know if the sill plates from a regular cab will work in a super cab?

1979...

 

Short answer, yes.

EDIT:
I'm suffering a case of "foot in mouth" disease. I was wrong.
According to the parts catalog Reg cab and crew cab are the same, supercab is different.
Regular and crewcab RH D6TZ-1013208-A, LH D6TZ-1013209-A. Crew takes two each.
Supercab RH D4TZ-1013208-A, LH D4TZ-1013209-A

 

regular cab has a different rear end(toward rear of truck) than supercabs, reg cab tapers down, supercab is just squared off across the back. from my experience it is because the seatbelt mounting is different on the floor and the seatbelt retractor unit is different as well

 

Thanks guys....

 

And that is the only difference. Regular cab sills will hit the seat belt mount on a supercab.

 

Well that's good to hear, I can make them work. I ordered regular cab ones when I did my parts order.