I always recommend using the Screw Mounted version of the JLD Bridge Doctor wherever possible – even on 12 string acoustic guitars.

However, that doesn’t mean doing the above pictured!

This customer’s review shows the screw being fitted directly between the rows of bridge pins – a very risky business! It’s such a tight space between the pins that you are just asking for trouble.

It’s why the Brass Pin version, albeit imperfect, is the best option for your 12-string acoustic guitar. There often isn’t enough room to drill the hole for the screw anywhere on the bridge. (Here’s an example where it could be done). You simply replace one row of the pins with the set of Brass Pins, with either the D or G pin (rather than the screw) screwing into the system block

Thankfully, it looks they got away with it – Phew! You’ll notice though that there wasn’t enough space to enlarge the top of the hole to insert the screw cover.

All I can say is, if you do choose to do it this way, do so at your own risk.