I'm thinking it's a model EG in 300 Sav, in which case if it has no collector status anymore whats the difference if it's D&T'd for a scope.
At some point somebody said that about every model of 99..
I'd leave it original, or maybe consider putting a peep sight on it. Pick up another one that's already been d&t'd by a smith (lots out there, I sure haven't had a problem finding them), or find a nice 1950's 99F that was factory d&t. Lots of those around.
