Dear GunGal80,
First thing that came to my mind was 'What makes you think that this is one of the Inspector Series pistols.' There were Nettleton series guns, there were Ainsworth series guns and maybe more.
Inspector Series guns were, to the best of my ever faltering memory, always marked with an inspector's cartouche on the left side of the grips and were never nickel plated. I see no such grip markings on the photos that you submitted. Is it the 7&1/2", original military issue style, barrel that led you to that conclusion?
I have an identical revolver that I ordered with premium walnut grips & nickel plating. It is not an Inspector Series gun, it is merely a representation of what any civilian could have ordered from Colt "back in the day."
Respectfully, CJF