Hi Paul, Euro spec E31s are very close. Its only the USA spec ones which were different (less options, dodgy headlights etc). Have a look at e31.net & e31faq.com too, that may help.
Well considering I replaced my thrust arm bushings 2 weeks ago...I would have to answer yes. But remember these cars are quite heavy, have immensely powerful brakes so the forces going through these bushings when you push hard is pretty big.
Re the wiper arms, not familiar with that problem. I don't know if the 540's do this but the E31's wipers retract under the lip of the bonnet when not in use to reduce drag so they don't really have a chance to hit the bonnet when in use. I have heard the mechanism which increase the wiper force against the glass when you reach higher speeds can need adjustment.
One problem at the moment is filling the 91 litre tank with Optimax..ouch.
Let me know if you have any more Q's!
Ian