8 3/4 vent location

In 1970, the distribution block was moved on the A body 8 3/4", further down the tube away from the center! This has gotten many people in trouble when ordering lines, so you need to identify which housing you have! Pre-1970 will have the splitter block riding up on the hump of the center a bit, and 1970 and later is down the tube a couple few inches! Hope this helps, Geof