Parts list is a bit vague, but maybe 67-7778, I believe Mikes'/Bretts above is not the one...Plunger ones have a bit that wraps around under the bottom and bolts to a frame lug...
Kinda like this one that's been slightly 'modified' ... out had some sliced off the vertical booty, but for some reason didn't fit like before, so chucked on a Hendrix one (generic one)...;