Bridge alignment holes. How to use them?

[Bowie]

I never payed much attention to these but, as I understand it, factories will use them to align the bridge when installing. I know there are plenty of other ways to align a bridge but I thought it would be at least a good idea to learn more about these and possibly use them. What actually goes in the holes (a dowell?) and can you give me any tips on using them? Is it as easy as cutting a little down and just fitting it in place?
Strangely, the stock bridge had no holes, but the guitar top did, and the replacement bridge does.

I made an arrow with tape to show you what I'm talking about.

Also, while I'm at it, this replacement bridge from Bourgeois came as-shown, with only two pin holes cut all the way through. The others are routed but there is a thin layer of ebony left at the bottom of the bridge pin holes. I plan to glue it in, then ream out the holes after drying. I've only re-glued bridges, and have never bought one like this. Any thoughts or advice?

Thanks!!

BTW, if the replacement bridge looks too large, it's just an optical illusion from the camera.

[mirwa]

Manufacturers use hidden pins for assistance in clamping, you find them u der fretboards and sometimes under bridges.

It means they can use a clear template on the guitar and drill the alignment holes, the bridge is likely cnc manufactured so the holes are pre installed, then they use plastic pins, steel pins or whatever they choose and they install these into the base of the bridge,you can then slide the bridge into place with glue and apply clamps with no fear of the bridge moving.

On aftermarket bridges they usually don't drillall the way through, as the bridge is being held in place whilst being cnc manufactured with vacuum, hence the almost through holes. You will likely find the person that made that bridge simply drilled the outer two so you can use your bridge pins to hold it on p,ace whilst clamping.

Steve

[Frank Ford]

In my opinion, there's no benefit whatever in using any kind of alignment through the bridge for repair. Simply place the bridge where it belongs, and stick some thick tape down to hold it there when you return it to location for gluing and clamping.

Works positively every time - and you can use the tape as thick and in as many places around the bridge as you want to avoid any movement:



The few times I've tried pins for alignment, I've found them to be less solid in holding the bridge in place.

[Bowie]

Thank you both for the advice. And, thank you Steve for the extra info shared in PM. Very much appreciated.