I ran into the issue where the mount screws were too long and would hit the "D" pillar when the hatch was shut.
I called Diamond for help finding smaller screws and they provided the measurements.
They are 4mm x 4mm set-screws with cup ends.
Originals provided with the purchased Diamond k400 mount are something like 4mm x 8mm.
I just happened to receive and mount the order from McMaster Carr and it resolves the issue PERFECTLY. No contact with the screws on the body to scratch away!
At $.33 each that would be $1.32 plus my research, processing and shipping fee :jk:
I left a detailed voicemail at Diamond Technical Support and missed the call back. It sounded like they would have sent the shorter set-screws for free.
Since they sell the original mount product I would try them first.
This is from their website:
Technical Information is not available through e-mail. Please call us directly at (770) 614-7443.
Technical hours are Monday-Friday, 10:00 a.m. PST to 4:00 p.m. PST. We are happy to help with any general questions you may have.
If that doesn't work, and it being the holiday season and all, PM me for my address and send me a self-addressed-stamped-envelope for a set.