So I'm in the Midwestspl local and I'm going to change my class to nationals and was wondering if any body on here is from the same group "Midwestspl" that in the basic 4 class that can tell me how tall my box can be I know it to the window line but my 2005 tahoe has to different window line heights the side window is higher than the back hatch window...more ? To come once that one is answer.