I "built" another of these today, using impromptu jerry-rigging techniques that would appall the likes of Charlie.
This poster was (and is) a mess, with several generations of old tape all over the back and front, pencil writing on the front, missing paper in many places, dozens of tears (some extending very deep into the poster), etc.
The poster is not worth very much, so I had to give it the Frankenposter treatment. I repaired all the tears with several dozen pieces of acid-free tape, cut off some of the paper ruined by old tape, slapped paper from another poster onto it, erased the pencil marks, etc. The end result looks reasonably-presentable now but of course is totally worthless with all the low-tech surgery I employed. (One more thing I could do is use Bestine to remove the old tape on the front, but I assume it would leave a brown stain.)
Before Frankenposter surgery:
After Frankenposter surgery:
This picture shows all the crazy tape and slap-on replacement paper: