I want to replace my batteries this year. I'll check and see if group 29s or group 31s will fit. Thanks for the tip.
One issue with my compartment is with even the group 27s in there now, you can't really reach the outside vent covers very well. But I bought one of those watering kits, so I should not have to access the vents.
The only thing that works on a RV is the owner...