Well, based on the serial number the blue Cyclepro ATB is definitely a 1983 Kawamura built frame. That's not surprising given that Kawamura also built Nishiki, another of West Coast Cycle's brands. In this case, there's absolutely no doubt to the lineage, as the shell has the WCC logo.

I'm also not suprised to see the bicycles coming from two different manufacturers, despite the close time frame. During this period, Nishiki production was split between Kawamura and Giant, typically with Kawamura handling the mid and upper range models while Giant concentrated on the entry level models. It's hard to tell if there's a difference in the level of the bicycles, as the blue one appears to have a replacement rear derailleur and forks, but conceivably the Dodsun frame is just a bit lower level, at a point where Kawamura was not cost effective.

I'm not sure that this is the case, but Cyclepro may have taken over the position of the Azuki brand in WCC's product line.