Need Suggestions for best tool for cutting bookshelf lip to fit a bed.

[king301]

Just bought a new house and the master bedroom has a bookshelf that wraps around the bed. As luck would have it our bed frame is about a 1/2" too big. Need thoughts on best tool to trim the offending lip. Its about 1.5" thick. Would like tool to make as clean a cut as possible. And the blade needs to be as flush as possible to get past the upright wood panel without having to angle the cut. Thanks in advance.

[Eric - TIA]

Not sure if that is wood or veneer.  I am guessing you are cutting that small part on the back of the shelf but not sure.  If so you can't get in there with a circular saw.  I would use an oscillating tool.  Just score the area you want to cut with a box knife.  Then put the oscillating tool on a slow speed and go over the area you scored to make a nice trench.  Once you have a good trench and you know the tool won't bounce around, you can increase the speed and cut through the wood.