Just lubed my wiper shafts so I'll post a few more notes.

-Once you've got the cowl panel off, stuff a shop rag down each side of the cavities by the fenders, especially the driver side, so nothing can drop down. Virtually impossible to see where it lands and, short of turning the car upside down, virtually impossible to fish things back out from the narrow crevice at the bottom, even with a magnet. I remembered this once happening to me.
-Remove the entire wiper assembly to the work bench -note the four T-washers on both sides of the rubber mounts.
-Next, memorize/document/mark the precise alignment of the motor control arm and linkage arms for reassembly. Presumably to take the tension off the wiper blades after the down stroke, when the motor is in the park position the short motor control arm ends up just a bit (like maybe 5 degrees) beyond being perfectly aligned under the linkage arms.
-Remove the circlip on the end of each shaft. There's a rubber o-ring seal under a metal thrust washer at both ends of the shafts -don't lose them. Check the o-rings for damage or excessive wear, replace as needed. If you've got suitably thin o-rings of decent quality then probably a good idea to always replace them as these act as lubricant seals. Probably best to avoid using standard thickness o-rings as they may create undesirable added friction.
-To be able to pull out the shafts, you need to unbolt the arm from the motor shaft.
-Clean/polish the shafts and bushings, flush the bushings and re-grease both the shafts and the bushings. Probably best to use a fairly thin consistency Lithium grease, but thicker than white spray Lithium.
-Re-grease the two ball joints on the linakge arms as best you can. The far end one pops off for full access. The middle one on the motor arm wouldn't pop off easily, so rather than force it I just regreased it under the rubber collar. There is no ball joint at the cable tethered end.
-Try oiling the motor shaft bushing with something like 3-in-1.
-The gearcase cover is riveted and cannot be opened, so nothing to do there.
-The cable tensioning nut should not need adjustment unless the cable pawl is noticeably floppy.

Made for a definite improvement.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now