In the College Course I'm taking, we use Beau's method. I applied the finish before gluing for Beau's reasoning.
We have a jig that precisely locates the bridge
Its clear acrylic, so you may not be able to see it too well.
It has a nut installed in it-place the nut in the slot of your neck
A centerline is scribed in it to keep everything centered.
There is a slot that the saddle fits in to locate it.
Drill 2 holes thru the bridge into top where G & A string go
Put small nails thru bridge to keep it from moving when clamping
These are just temporary.
Glue and clamp. I used opposing wedges under the caul to keep clamping pressure on the 'wings'
DISCLAIMER: this is my first build, but the Course instructor has years of experience.