I pre-installed LMR-195 coaxial cable to the bottom portion of the 3/8 inch NMO mount and pushed it up through the hole. This is the classic difference between the 3/8 and 3/4 inch NMO mounts. The 3/8 inch NMO must be installed from the bottom while the 3/4 inch NMO mount can be entirely installed from the top… often a serious advantage. I had bottom access so I opted for the superior mechanical strength of the 3/8 inch NMO mount.
