Possibly a dumb question, but are you sure you have the right mounts for the correct year block and K Frame? There are different mounts for 73 and up blocks, so it may be possible that either you have a 73 and up block, or maybe they sent you the mount for a 73 and up block packaged as the 67-72 version. I have a set of /6 to BB for the 67-72 at home I can take some pics of if you need them to compare.
