My drivers side vent window (the triangular one) in 87 Westfalia is
leaky and noisy.  I've tried "adjusting" it while the window is open and
then closing it, no use (as I suspected).  I assume it needs to be
replaced.  Is this an item that can just be pulled out and stuffed back
in, or is glue/etc required?  I see also there is a "grooved" and
"without grooved" version, how can I determine which one is needed?  I
looked for groove and dont see one, except for where the window sits,
but I am not sure what to be looking for.  Thanks