Graflex RB Focus Adjust

Just picked one of these up and have a Polaroid 405 taped to the back. The focus is off on this so I've shimmed it out about 1/8" but it's still funky. Is there a way to adjust the focusing screen?

you need to move the ground glass up as much as the polaroid film plane is back from the film plane of the camera with normal film holders.

You need to move the polaroid film plane to the camera film plane.

RB in a Graflex SLR name donates Revolving Back. There are severas models with a Revolving Back. All Graflex SLR's are a variation on a theme. Each model has its own size in a given format and range of lens that will work on it. Some lens within a given SLR's range may not work due to their focusing charctericts. The view ground glass can be adjusted 1m to 3mm on most models. The film plane depth on Graflex film holders is the same as their standard film holder counterparts in the format size. A lens can be shimed outward a few thousands or recessed into a lens board to help in compensating on the focus distance difference between the view ground glass and the film plane.
More information is needed for specific suggestions.