Cris,
The photos in your first post show Middle Park Lumber Co. 684, a 45 ton, standard gauge Class B (2 truck) locomotive built in 1906. The buyer used the builder's serial number as the road number. This was Climax construction number 684. According to the link to the Climax Locomotive page, this locomotive was photographed by Otto C. Perry in derelict condition at Fraser in 1927, and the locomotive was scrapped in 1939.
Colorado & Northwestern No. 2 was built in 1897. It was a 50 ton, 36 inch gauge Class C (three truck) locomotive. I believe this was the first factory built three truck Climax. It was sold by the C&N to Pacific Contracting (White Pass & Yukon Route) in 1899 as WP&Y 8, later 58. Sold to Maytown Lumber Co in Washington state in 1903, reportedly scrapped there. Kramer Adams' list of logging railroads shows Maytown Lumber Co operating near Tenino, Washington with five miles of track one geared and one rod locomotive, with earliest reported date of 1912 and last report in 1924.
Summary - the Middle Park Lumber Co and C&N locomotives were quite different.
Good luck with your project.
CVM
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