Forgot to mention - your binding colour question. I have the opposite problem as my pickup mounts are white. When I layered my truoil the binding took on the amber colour which looks more cream now vs white.
I have been tru oiling my pickup mounts as I go so the colour matches the binding.
Simon’s tip around 3m tape is the best way to get a clean line but I found I still need to scrape and sand the binding to get a clean line. I found that it was easier to mask the stained body and then sand the binding to get a clean line vs trying to get a clean line when first staining. This is the weakest part of my build so listen to gurus like Simon and Mccreed