A '41 to '46 Chevy/GMC has a front of about 57 inches and is about 72 inches over the front fenders.
'46 Chevy dimensions A '47 to '55 1st Chevy/GMC has a front tread width of 57 inches and is just over 72 inches wide at the front fenders.
'54 Chevy dimensionsA '55 2nd to '59 Chevy/GMC has a front tread width of 61 inches and the width across the front fenders is just over 74 inches.
'59 Chevy dimensionsI don't have a ready source for '60 and later data, but I suspect you'll find that a '60 or later is the easiest fit.
