I use 3 of the Harley locks.
One for the luggage rack, one for the backrest, and one for the tourpak

 

I use the Harley locks. Seemed like it would be to easy for a theif to just unscrew the lock from the attachment so I used red loctite and then filled in the allen head part of the screw with epoxy. Figure it will be permanent anyhow.

 

The MoCo makes some windshield Quick Release Clamps locks. They make 3 or 4 of them but really didn't look too much into it. Not sure if it's model specific but it's a start for you to check out.

YB

 

this is the one i have. works great. but that little security screw is a small bugger, easy to drop.

 

I have ESM's "Clamp-it-Securely" http://www.esmmfg.com/. $10 I feel much better when its installed because the thief must have a security torx to get it off. Skratch is right, however, fastener's a little bugger.

I've heard lots bad about the HD lock that takes a key. Jamming and stuff.

 

Our Brukus Tourpack BULLET Secure secures your detachables and here is the link to the HDForum Discounts. Our Bullet Secure blends right in to the hardware.

 

We make 2 styles to secure the detachable windshield - called our ShieldShackle. ShieldShackle for the Road Kings and Switchbacks, and ShieldShackle for the Softails.

And again - here are our Brukus Discounts for all of our products.