That sort of tape is nasty stuff once it gets old. The stain probably can't be removed without a ton of effort, that would go beyond preserving and into altering (To me anyway, opinions differ)
I'd put some talc or corn starch or similar powder on the adhesive residue to keep it from sticking to whatever holder it's going to be in and just letting it go at that. One of my 59Topps Commons has tape adhesive, and it's been sticky since at least the early 90's. I made a few attempts at removal, and nothing had any effect at all.
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