retiredoz, My microfische starts at 1957, and it lists both RD-19 and RDE-19,as 1957. This lower unit that I took off the RDE-19, had the shorter lower shift rod in gearcase, which is why shift arm was a hole off, and wouldn’t line up. I took lower unit off the RD-19, measured the height of shift rod and it was 1/8" longer, put that lower unit on the RDE-19, and everything lined up, shift arm in correct position, and shifted good. I just removed the lower unit on my Evinrude Big Twin, checked shift rod height, and is the same as the RD-19. I am going to take the shift rod off Evinrude, and hopefully will work on other unit. I was wondering what was the reason for the shorter shift rod was? Apparantly, the upper shift rod doesn’t change, because the other lower unit on the RD-19 seemed to cure the problem. Do all these lower units use the shorter shift rod from 1958-up? Otherwise, they look the same to me. Just like a jigsaw puzzle. Thanks, Gene.