I'm about to do the same, again. Didn't know there was a rh/lh piece. I installed them once by positioning the shorter end into place and then bending and sliding the longer (rear most) pieces into place. They look good but lid won't stay open even in the max setting. That's why I think there's a rh & a lh. Oh by the way in my '67 Ford shop manual a nice pic and a "how to do" showing the special tool. The tool looks eay to make as that's what I'm doing. Flat steel stock about 1" wide, make a slit in the end about twice the dia. of the rod, then a hole center of rod couple inches down the bar, be the same dist. as the small end of rod where the "U" shape is. Just slide on tool and twist I guess. Haven't gotten that far yet. When all else fails use a pipe wrench and a big adjustable wrench.
If you borrow a tool more than twice, you need to own it
You get what you pay for!
George email: <firstname.lastname@example.org>