I recommend this stuff. Scotch double-sided scrapbooking tape. It's strong enough to hold the mounts in place, but is removable so you can re-position the mounts if you need to, at least for the first year or two. After that, you can still remove the mount, but you'll probably need to replace the tape when you reattach the mount to the page. It comes in "removable" and "permanent" varieties, but both are removable – I use the "permanent". Been using it for about 24 years without issue. NOTE: this is NOT the ordinary Scotch double-sided tape! Don't use that.

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