The Triumph Manual says to remove the swingarm , you don't have to .
1. It's easiest to get the bike up straight on a center stand or whatever instead of leaned over on the side stand .
2. Now remove the seat ,left side cover, the pc of air box that the snorkel goes in ,left exhaust, and chain gaurd.
3. Loosen the Chain
4. Remove this bolt from top of swingarm .
5. And the one on the side , it's a little awkward to get at but doable
6. Now with a pair of channel locks grab it and yank
7. Stick the new one in and use something with a blunt end to tap it home , it;s a tight fit,
8. Check the rub block while you're here
9 . Put everything back together in reverse of how you took it apart.
These are supposed to be replaced every 18 = 24k but I don't think tigger 3 ever got done once cuz it came out in 3 pcs and wasn't much of it under the chain
I replaced mine last winter at 24K miles. I think that interval could easily be doubled without consequence.
I did not remove the swingarm, either.
What kind of shock do you have on that one, Mustang?