It gives you an idea but it may not be totally accurate. I assume these screws thread into your gauge. Do they seem to fit fairly well with not too much play? If so, I would try a screw that should work in the holes where the missing screws go. You should be able to determine the correct size by the inside diameter of the holes as compared to your gage. It may be that not all the screws used in this item are fine threaded or even imperial. Hope this helps. Paul M
