Rob,
I was, until my retirement, a Chevrolet Technician for 24 years.
To the best of my recollection the transition to a "gold" plated bowtie, as the emblem is affectionately called, started late 70s to early 80s and was pretty much complete by the mid 90s. The blue was discontinued with each older body and gold introduced on its replacement.
It had nothing to do with the acquisition of Daewoo, rather a design and cost of production decision.
Time has blurred my memory, but I hope this satisfies your curiosity.
Rich