I usually go to this one before I head over to Nonthaburi Immigration to get my Bank Letter and Passbook updated before extensions, it's right around the corner from my house, and I believe it opens at 8:30am. It's usually not too bad of a wait, just have to park a little bit before the 7-11 (100 yards short of the entrance), as parking in front can be hard to find.
https://maps.app.goo.gl/JHUdF8prKiuLy1nK9