67 Door window glass question

[indianajoel]

My window regulators on the driver's side keep going bad.
I just bought a brand new regulator and don't want to ruin it, so I was inspecting everything else and had a thought:

Is the left window glass different from the right?
Like if they are a little curved in towards the truck as they go up.

I put a straight edge on them and they are slightly curved - about 1/16".
but the right one is curved in towards the cab and the left one was curved away from the cab, with the convex side of the glass facing into the cab.

Could that be a problem causing my regulators to grind teeth?
or maybe the 1/16" is to small to be a big deal.

lmctrucks lists one door window glass without the frame -- no left and right side distinction.

My left side glass didn't seem to be seated all the way into the sash channel on one end, so that could've been what made the window tought to move.

Thanks for any advice.

-Joel