Installed a Joey Bed in the Marathon pass through bay this weekend. I purchased a 90" two way bed and was able to achieve 34 1/2" in width. The width is adjustable from about 30" to 48". If anyone does one of these, be real careful on your measurements before ordering. You will need to get in the bay and have someone close the compartment doors to get an accurate length measurement. The Marathon has chair compartments built into the bay doors that take up almost 4". When it was all done, there was exactly 1" clearence from the bed to the doors. The whole job cost 525.00 including 3/4" plywood, carpet and paint.