Here's a link to various group sizes of batteries and their demensions. FWIW, the 40R, (not mentioned) has one of the highest AH ratings of them all, with lots of room to spare. Sears also has a 5 yr warranty, no questions asked for the 1st 3, then prorated thereafter. Don't forget to cover the underside of the cover (or battery terminals) with non conductive material!

http://www.batteryweb.com/bci.cfm.

Troy