First....do NOT laminate either of the documents. It will ruin them. Make several good copies of both, to use as display items for shows, etc. if you plan to show the car. Laminate the COPIES, if you wish.
Your best bet for protection is to keep them out of any light, as much as possible. A protective sleeve is good, just be sure the sheets fit loosely....not to tight, as you want to be able to remove them if needed without tearing them.
Other than that, I can't help. You might check with your local library to see if they know of a local paper conservator that could give you more help in preserving these documents. Please, Guard and protect them!
I'm a great proponent of keeping/preserving historical documents when it pertains to Corvettes...we need to save as much as we can for future Corvette aficionados.
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Joel Adams
C3VR Lifetime Member #56
My Link
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"