well i got down and measured the '63. the pitman arm looks to be about 5.5" from center to center and 7 3/8" overall lenth. the idler arm is not in a single plane it is offset a bit. so it looks to be 6.0" center to center and 7 5/8" oal. i had to break out the 18" calipers to try to measure it. don't hold me to those #'s but looks to be pretty close. lmc catalog shows same part #'s for 63 and 66. good luck, hr
