All you need is a 3 foot ruler, like an aluminum carpenter's ruler. Or some kind of 3 foot long bar with a straight edge.
Put some masking tape down on the body , about where the bridge should go.
Place the 3 foot ruler against the side of the neck, touching the fingerboard right at the nut and at the heel. Make a pencil mark where it crosses over the masking tape. Do the same thing with the ruler on the other side of the neck, make another mark.
Draw a line between those two marks. Measure the length of that line and divide by two, mark it. That's your centerline side-to-side.
Measure the distance from the inboard face of the nut to the center of the 12th fret. On a 34" scale bass, it will be 17". Measure that same distance (17") from the center of the 12th fret down onto the masking tape; make a mark. That's what we call the Zero Line, the theoretical scale length point.
Now, take your bridge and adjust the saddles almost all the way forward. With the saddles forward like that, place the bridge on the body so that the witness point on the saddles is right over the Zero Line, and the bridge is centered side-to-side over the centerline. Check to make sure it's square in relation to the centerline and the neck. That's the position. Mark the holes.
Sometimes it helps to mark and drill the center screw hole only first. Screw the bridge down with just the center screw. Then stand the bass up vertically and step back a few feet. Adjust the bridge until it visually looks square and right. Then, mark and drill the other screw holes.
A laser???? Really? I thought you were joking, Matt, but I guess not. I guess I'm just an old fogey, but I kind of prefer a ruler and pencil for lining things up less than 3 feet away. A laser seems like an excessive use of technology. But, okay, if it works....