Defender wiper system comments sought: knock in right hand Wheel Box

[Lawrie]

I have started this entry as I did not find any related.

1984 Defender ROW spec- RHD.
wiper wheel box on right (driver) makes a succinct "knock' every cycle (wiper is unobstructed, normal sweep). This is loud, heavy thunk.
Motor running fine, passenger side fine.
Shaft does not move too much (i.e. wheel box is secure) but play is evident.

I assume the wheel box and/or drive cable is worn. and I should buy and replace?
The gear wheel - as part of motor/cable drive may be okay as no sound, obvious play over the on left side
Or do I assume this is also worn?

Any tips, thoughts would be appreciated before I tear into it (trying to have what i need at the ready as it is a daily driver).

Thanks

[thewap]

Probably the wiper wheel box?