One of the 3-4' straps should work just fine. One of the heavier gauge straps will increase the capacity of your 2x10 significantly. It will take quite a few screws or you could opt for 2x12 boards. I've seen a 2x12 bend slightly but never have I seen it buckle.
91 TT 02 CBR954RR
Who cares if its free? If they give you a free didlo that doesnt mean you shove it up your ass! --- NIXIT @ Rib Crib Sept. 2003
Please step away form the car... You're blocking the view. --- Tu (in reference to ugly hood ornaments)