Mine appear to be permanently mounted to plate which is in turn mounted to the standard, rather than just a vial that pops into a standard, the former I gather is the way it's done on the F, while the latter (so much easier) is for the F1, F2, etc. I need the former for the10 back standard, horizontal level vial. Also, I am missing one screw on the mounting plate.
Can you help me supply or source this? Thanks in advance!