Service it?
You do realise that even specialist BMW independents usually won't service them, as hardly anyone knows anything about the V12.
That sounds very much like the opinion of someone who hasn't seen an M73 in the flesh, let alone worked on one. It is a 4 stroke Petrol engine, not a nuclear fission reactor.
Bar changing spark plugs, servicing is business as usual, and even when it comes to spark plugs, 10 out of 12 are painless, one is slightly awkward and one (Plug 12) will have you struggling for a while but it isn't particularly difficult once you know what to do (is it far easier to change the rear most plugs on Arrange based cars underneath). One of the first jobs I did at my dealer's was a service on a silver seraph (same M73 V12 found in the E38 750), and I distinctly remember thinking to myself once it was done "That isn't nearly as difficult as people make out". I'm not saying that because I'm some sort of super mechanic, I'm saying that because I genuinely didn't have a problem (Bar plug 12!
).
I've helped have the inlet manifold (Plus rocker covers and other bits, but I can't remember what we were doing to it
) off of a M73 and it was genuine a pleasure to work on - It is best to think of it as two simple, separate SOHC engines with a common crank, that's properly because the original M70 was essentially two E30 M20 Six cylinder engines with a common crank.
And out of all the Bentleys And rollers I have stumbled across, the V12 seems to be the most mechanically reliable engine in the range.
As for those who say that the 750 is pointless because the 740 offers similar performance, you gentlemen have COMPLETELY missed the point of the V12. It's key attribute is its smoothness and progressive power delivery (not to mention the noise!!!). Wafting wise it kicks the Turbocharged 4.4 M62 V8 in early Arrange cars into next month.
Gah! I want a E32 750IL now!