what size bags

ok this is probably a stupid questions, but I have and 84 s-10 and its getting bagged... I bought 2 slam bag 2500's, and 2 slam bag 2600's.. will the 2600 be able to compress completley, it says it takes 400lbs a bag. please help so i dont get stuck sending them back.thanks

Steven Judd, Vice PrezAllusive Dreamzhttp://www.geocities.com/allusivedreamz