Shims are available, and the shimming instructions are in the manual
We always skim heads
To remove the pumps, push the stop lever across to the stop position, that aligns the lever with the hole in the casting to remove them. Unless you want to reset them which needs a special tool, best to remove them one at at time and put the pump back when you've finished with it. Stop lever to stop, put the pup in and twist anticlockwise before clamping down. It often isn't that easy...
Email received, I'll get Sue to call you
Richard