I cut one 2X8 about 12 1/2" at the base with a slight angle on each end. Many times this board goes between the tires when I need to back up onto boards. My second 2X8 is about 2" longer at the base. I've never needed to raise one side of the trailer any higher than 1 1/2" so these two have served their purpose adequately.
'01 2500hd ext. cab, 8.1 litre gas, 5 sp. Allison auto
3.73 rear end
Mag-Hytec rear diff cover
Amsoil Dual by-pass oil filtration system
Amsoil synthetics all around
265 watt AM Solar, Inc. system