as a former iRobot intern of 2.5 years, I welcome you (back) to FRC
Most teams will make each bumper segment separatly. Dropping the whole thing over the top is not a bad idea, though, and is perfectly legal.
All the teams I have been on do not attach the noodles to the board. The fabric holds them in place. Actually, using anything except the fabric might be illegal (look up the list of "soft" parts that can be between the backing board and the rest of the world.)
One year (2008, team 1318), we successfully "chained" each segment to neighboring segments with a door hinge. A wing nut on each far end was all we needed to hold the bumper on. once the nuts were off, the bumper could be unwrapped from the robot.