infiniteMPG wrote:
....
Some of the board parts have a high shine to them and other parts are
very dull and flat. Was just differences in parts of the wood ...

Mostly it's the difference in that you didn't sand it all uniformly
before putting it up, did you? Nor did you use a sanding sealer to help
blend out the differences, I expect.

What we were wondering is if someone could recommend maybe a satin
clear protector or something we can spray or brush over top of the
stain, not only to protect the wood, but also to unify the finish
appearance. ...

Unfortunately, the only thing that will "unify" the finish at this point
is paint--it's too late to compensate for what wasn't done initially.

The only way for sure is to sand it all to a uniform grit, apply a
sanding sealer and then restain. Not what you wanted to hear, I know.

A varnish or other clearcoat at this point will on accentuate the
differences, not blend them.

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