Someone mentioned that it is possible to remove the keel and lie the boat at an angle on the trailer to meet width and height restrictions. I'd appreciate any suggestions and information, especially regarding cost.

I am pretty sure that this will not get you around the width restrictions and for height, the boat on a trailer should be fine on all interstates. We just moved ours from MN to WI on I-90 and I-94. Had to get a wide load permit for both states (through an expeditor it was just under $100 - included both states). On the trailer, the boat with the rig on top, was 13' so no problems on the highway for a 300 mile drive.

We just trailered the boat from Mi. to La. and back. Pulled permits in all states for the width; boat was 12'11" high.
No problems.

Trailered it from Mi. to Key West and back several years ago. Had it hauled from New England to California and from Cal to Mi. Never once even thought about pulling the keel

so ok ... maybe on a Melges 32 ... but not on a j30.