1981 P30 drop spindles

[Rocketdawg]

Does anyone know if drop spindles for a 1981Chevy C30 would fit on a 1981 P30 chassis? I can't seem to find any listed for a P30.
Thanks!

 

[Rocketdawg]

I'm also needing to change out the springs for something lighter as the motor home that was on the P30 chassis is now gone. Does anyone know if springs from a C20 would fit? Or does anyone know of a direct replacement air bag kit for the front?
Thanks!