I understand that a Polaroid holder can be fitted to the Series C Graflex. Anyone know which holder can be used, and what mods are necessary? Thanks. Arthur

The base holder is the 405 holder. This comes with a metal plate on it that fits 4x5 cameras. Take that off and make up a 3x4 version with the proper slots for the light trap and it might work.

I was able to permanently modify a Graflex back from a 3x4 Anny Speed by removing the metal rail at the bottom and opening up the back slightly. Then the Polaroid back would fit the Graflex back directly without a flange. I still had to adjust infinity focus on the RF which I admit is easier to do on a Speed than shimming the ground glass on a Super D