My '80 GL1100 has an 18" front wheel instead of the original 19" (PO mod at some point), and the stock 17" rear.
A guy on craigslist was parting out an '82 GL1100, and I picked up a spare 76K engine (for $50), and also got the front 18" wheel/tire, and rear 16" wheel/tire ($20 for both and...