Torsion Bar Install

the last 3 digits of the part #'s are stamped in the end of the bar....if the last digit is even, its a right side bar and if its odd, its a left side bar. The newer ones I've seen are stamped R and L too. I've read that the numbers are in the anchor(x-member) end, but I've seen part #'s on both ends with a date code on one end and letters on the other end, so i assume the date coded end goes to the back?