No, once the standpipe came along (first version in '62) Chrysler put the standpipe on every Slant-6. Aftermarket pumps have pretty much always come without the standpipe -- they just have a male/male thread adaptor to mount the filter.
Maybe that's what I am thinking about. I knew somehow I had seen some missing.
Also I'll add this.......for "whatever" it might be worth. I've noticed a difference in the location of the oil pressure switch on some models. Some are mounted in the block, like my 64 and some I've seen screwed directly into the oil pump. The ones in the block could take a few more seconds to see pressure, I would think. Like I said.......for "whatever" that's worth. Probably nothing. lol
