I raise my X5 from front center with the stiffen plate all the time. I use a block of wood to fit up in the little space. They make a piece of aluminum designed just for the X to fit into the body corner lift sockets that would work perfectly for the under engine center lift.

I doubt you can get to the exhaust bolts without removing the skid plate* anyhow and it's only 6 bolts so it'll be one of the easiest parts of the job. Just put the back four in so you can test drive before putting the stiffening plate* back on.

* The plate has multiple jobs but it's easier to type skid.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)