I'm replacing a half dozen board ends in a hardwood floor due to water and carpenter ant damage. Each is about 4-6" long. I have the old boards cut and removed, and in fact I can slide the new boards in from the ends, and so don't need to cut off the bottom of the groove edge of the boards. But, the floor was at one point sanded and refinished, so the new boards are about 1/32" proud of the main floor.
Should I sand down the new boards to the correct thickness before installation? Or, should I install them and then sand them in place? And the same question with polyurethaning the boards: before or after installation? (I'm worried that sanding or getting finish on the old boards will make the repair more visible.)