(2) Mustang Museum's

[Qikbbstang]

I doubt many Mustang fans that get their share of Mustang and Ford Shows will plan a trip/shell out money to see a private collection of less than 150 Mustangs spanning 1965 to present. Going to be tough getting that investment pay-off. 

http://www.mustangandfords.com/news/1605-after-15-years-of-waiting-mustang-enthusiasts-will-finally-have-their-museum-or-two/

[Autoholic]

If you want to see muscle cars from all makes, there is a private collection near Denver. I'd have to do a lot of searching to find it, I believe the owner allows visitors upon appointment. I've always wanted to try and visit it.

So there are a few collections in Colorado. One actually is a huge classic car dealer.

http://gatewayautomuseum.com/

http://steelaffairsautomotive.com//