Certainly sounds like the compression rod ball joint.
Compression rods and seating cones are in stock and good to go same /next day.
Just drop me a PM if I can help further.
Alex.
Are these motors not aftermarket ?
Genuine Nissan new power window motors are only £179.00 from forum traders.
Worth paying a bit extra for the genuine article and a local warranty IMHO.
Yes agree not much room for that one however certainly doable in situ. trust me.
Otherwise if you can not find any one with the suitable skills or desire, then just slip the engine and gearbox forward an inch which would take about an hour, but really this should not necessary.
All 10 bolts on the L/H bank are accessible for removal if broken, granted the rears have less room to work around, but it is certainly doable with out taking off the head, providing you have the correct tools and a little skill.