I don't know if it's possible without removing the exhaust, but I can say that for my 2001 3.0i, dropping the exhaust was way easier than I expected. I found I needed to do that when reconnecting up at the exhaust manifolds following some engine work. I wrestled with things for a while trying to find that extra inch needed to connect the exhaust to the manifolds/cats, then gave up and dropped the exhaust, and it was pretty easy after capitulating. Big, etc., so I used milk crates to support the removed sections, but the bolts all came out easily, went back together easily, etc.

Separate question ...
At 197k miles, I've got no problems back there, but the rear CV joints and rear driveshaft CV have never been touched. So I was thinking of pumping in some new grease as I often do with old CV joints that don't need anything other than grease.

Is there any reason I can't inject new grease through a gap between the rear driveshaft and the rubber boot? Of course also draining old stuff out of that same gap. Rear end jacked to let gravity help me. I'd prefer to not remove any parts or nuts/bolts if I don't have to. Removing panels, exhaust, etc. down there I'm not worried about.

I followed your links to your 528 DIY tutorial, etc., but still have this question. Thanks for all the info.

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2001 X5 3.0i, 203k miles, AT, owned since 2014