I have a 30-31 repro roadster body and would like to install the windshield frame and stanchions. My problem is that the lower stanchions that came with the body are not drilled/threaded and need to be so I can mount them to the body. Can anyone tell me the size drill and tap to use and how do I line them up for mounting on the cowl so they are properly positioned ? I want to make sure they are in the correct position so the top will fit correctly when I install it and that the windshield frame will fit between them also. Is there a template available to do this ?