I think the real trick is taking a real long time and getting the masking done really, REALLY well. I paid a lot more attention to that on the second try and only would have had a couple of very small places that needed any scraping, but couldn't get the color to even out, as it darkens as you layer it on.
You learn a lot doing different unique kind of projects and working with different finishing materials; if you want to use the ReRanch Goldtop Gold be prepared to to do some sand back at first as it takes a little bit of spraying to get the hang of laying it down. There's NO lacquer, you're laying down a metallic layer that needs to go down all at once and sprayed in very light passes to build up the finish. It dries really quick but if you barely touch it you can smudge/put a line through it and really need to start early in the day so you can get all the Goldtop down and still have time to start spraying at least a couple of lacquer coats to seal it after doing any scraping, but the KEY is to get the masking as near perfect as you can so as to minimize the need to scape anything.
At any rate, if doing a finish anything like this project, here's what is working for me:
1.) Do the different finish on the sides/back of the binding FIRST, masking the binding off in that direction is real simple, you don't need to worry about the top at all and it's relatively easy to mask off the binding from that direction and just use wider tape and score it and fold it over the top. 2.) Fill and finish the sides and back through whatever process/finish you're using through the first few coats of whatever top finish you're using.
3.) After stripping the existing masking back off, start tearing pieces of masking tape off long enough to generally follow the curves of the top, you'll use longer pieces on straighter parts and shorter pieces on the tighter curves, Press each piece down and rub it against the binding so that it clearly shows through (use regular masking tape instead of the blue).
4.) Using a SHARP X-acto knife CAREFULLY score the masking tape at the very edge of the binding that you can see through the tape and use a fingernail to pull up/separate the tape at the scoring and pull off the part overlying the top. This is easier to do one piece at a time working your way around the top. It is tedious and exasperating, and you will have the tape tear in places and have to redo it that section over. Once it's right, press down the tape over the downside of the binding.
5.) Continue this process all the way around, then just liberally apply additional masking tape all around to mask off the entire side to the edge; as it's already been lacquered getting it back off is no big whup.
6.) Shoot your top finish till you get it where you want it to be...
7.) CAREFULLY pull all your masking back off; start at the point where you started and most of it will come up attached, there will be a few small pieces you will need to scrape back off with a finger nail.
8.) Score the sharp outside edge of the binding per the instructions above from CB and sand the edge smooth.
9.) Hopefully there should be almost nothing that needs to be scraped at this point, but what there is needs to be done at this point should be scraped.
10.) Shoot your lacquer or other top finish coats.
Again, other can chime in, but from my experience so far the secret of binding scraping is to spend a LOT of time/effort masking as to reduce the need to scrape anything to the absolute minimum.