Wheel alignment tips/info

[c-bass]

The wife's X has the all too familiar "stance" in the rear and seeing as she's got fancy snow tires on there I'd like to try and prevent them from wearing unevenly.

I've got an appointment booked tomorrow at a shop that does a lot of work on lifted jeeps and trucks and I figure they'd know their way around, but just in case they've never dealt with an e53 before I'd like to come with some info that might help the tech and not come off like some prick telling them how to do their job.

There's bits and pieces here I've read over the years but I can't remember any of the info off hand.

What's the low down on getting things dialed in properly?