It's not unusual for the dates between the frame and head badge to be separated. In this case, the badges were most likely stamped in the US and sent to Tawain for installation on the frames. Of course, this is just my guess.
The High Sierra is a great bike and they make for great builds in various configurations. Mine is a yellow '88 and I've added fenders, racks, and smooth tires.
Can't wait to see your HS cleaned up. Smoked chrome is fantastic.
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Bob
Enjoying the GA coast all year long!
Thanks for visiting my website:
www.freewheelspa.com