If you can see on this 'period' picture (about 199 my Alpine Trail is sporting a brand new, aluminum, all box section swingarm. This is a second generation swing arm. They were doled out by ATB Sales when the original steel one bent (as they all did!). Still no disc tabs.
So, between all these posts you have four of the five single pivot FRS swing arms. The 2000/2001 swing arm was a smaller strut design much as the 1999 one. After 2002 model year, they switched to the Quad Link design (correct me if I'm wrong).
Now, does anyone have a Fox Alps 5R, to fit a '98 model, I can buy?!