Another item from the Capri-list archives, originally written by Ted Szypulski:

Sometimes lightning does strike twice in the same spot. I was looking at my daughter's 1989 Volvo 240DL wiper arms one day and suddenly realized the plastic end caps were EXACTLY the same at those on my 1976 Capri! Now, there are various wiper arms on Capri's, so this won't apply to everyone. I have a 1976 MKII with black wiper arms. They mount on splined shafts and are secured with a hex nut. There is a black plastic cap which slides into the arm hinge and snaps down to cover the nut. This is the cap I'm talking
about here. Mine were weather worn, turning white, and one was cracked. I paid $6 each for two used ones last year. They were not cracked, but they were weathered and turning white also.

Well, I purchased two of these new parts from a local Volvo dealer and the are PERFECT replacements. And if that weren't enough, they are only $5.37 at LIST price! That's less money for this brand new part than I paid for worn used ones! The Volvo part number for these is 1392918-7. Be careful to order this specific part because Volvo used two different end caps in 1989 and this is the correct one for your Capri.

A word of caution on removing these covers -- the driver's side arm is most prone to damaging these caps when you try to remove them. That is because this side must bend more here to conform to both the shape of the windshield (windscreen) and the axis of the pivot. The passenger side is more in-line. When you install or remove the cover at this end be very careful not to rotate the cover up too much before pulling it away from the arm. If you do you will snap off the end of the cover as it hits against the wiper arm.