I've built the section of the table that flips. On the saw side, I have 1-1/2" to build up so the bed of the saw is flush with the rest of the table. How would you attach the saw so it's secure to flip upside down?
The top only has holes at the front, for inserting a side clamp.
Maybe bolt through the ends into a block underneath?
Yes, I would use machine bolts through those holes there. You may want to install some one-by underneath, but you can probably get away with just the plywood if you use a fender washer on the underside. I would also recommend a washer under the head of the bolt.
Yeah, that should be fine. It’s not exactly a massive saw. If OP wants to go “belt and suspenders,” a couple of U-bolts in the mounting holes for the old rod extensions might also be helpful. I think even a single generation later, most miter saws had proper mounting holes, though.
You could countersink some carriage bolts from the other side to hold the miter in place, with the appropriate height block in between to set your height.