Plan ahead. You know there's a blind spot on your right from about the rear axle to the front bumper so check traffic before hand to give you an idea there might be a problem that will require added attention. Slow down as you approaching the exit and broadcast your attentions. If you have a second person use them as a spotter. Most of the time you can see what traffic looks like on the ramp as you're approaching and can estimate if someone might end up in the blind area. Be ready to abort and take the next exit if possible. When driving a coach time should be the lowest factor on your priority list.
You could also add an additional mirror on the right for the blind area. You won't be able to read a license plate but you'll know something is there.