There are a couple guys on meanchicken that could probably give the history. There might even be a build thread for the tower, River boats are pretty interesting. It was the 60’s when they got into aluminum and almost all those builders knew each other for a long time. A lot of the builders worked for and with each other at one point, it’s still not uncommon that someone building boats came from custom weld , riddle, or bentz.
the Idaho builders gravitated to boats with a lot of lift and ride high in the nose. Oregon ended up with quicker boats that flatten out at higher speeds and carve corners.
you might give Wetever in Clarkston WA a call too, They are good guys and may get you started,