You have a nice batch to work with. Very good amount to process. If it were me, while it's very cold outside, I would do this.....
Put the fingers in a 5-gallon bucket that has holes in the bottom of it, placed in another 5-gallon bucket, add HCL/Muriatic Acid, add no more than 3 cap fulls of Peroxide, and with an air bubbler, add the same amount of distilled water to the solution.
With the air bubbler and the water to dilute the solution, you can let the fingers sit in the solution for a month or whatever, and when you are ready to work on the fingers, the most you'll need to do is pick through all the fingers that are completely stripped of the foils, without dissolving the gold, and not having to check on it until you're ready to process them.
Just be sure to have a copper bus bar to collect any possible gold that may dissolve. But if you double the solution with the distilled water, the most that would probably happen is that the copper would dissolve and you'll probably have nothing but gold flakes and some blank fingers in the bucket. The rest of the fingers may be loose enough to just use a toothbrush to remove the other foils, without ever using any heat. The air/bubbles are the keys when letting items sit in solutions without heat.
scrapparts.