the question is,are you confident with the 6 foot weld seam? are you paying someone to do the install or doing it yourself and have plenty of time and patience? I ,without a doubt buy full quarters ,it will be alot faster and job will be much cleaner,ridding of issues that might show down the road,
BTW,if you need a quote for your sheetmetal needs,PM me,I can get you great prices on AMD stuff