It appears that 70-71 240Z used one type of turn signal switch, and 72-73 used a different one. Anybody know what the differences are? Assuming that originality is not crucial, is one better than another?

I ask because I will be needing a replacement for my 71, and used switches from 72-73 seem to be more plentiful.

You are right about the later model ones being easier to find! The only difference that I know of is some of the wires on the later ones are longer than on the early ones. May be other differences that I'm unaware of and I'm certain that if that's the case someone else here will chime in.

Length of wire loom on the sw assembly, and connectors are slightly different.

So no difference in how the dimmer switch works, or anything that would preclude using one if I'm willing to do a touch of re-wiring?

I have a 1970 and some of the wires came loose from the solder on my turn signal switch. Can anyone take a picture of the back of the switch and email it to me so I can solder it correctly. Thank you. ricksaia@hotmail.com

No difference in function. If you are careful & somewhat skilled I believe that you could make one work in place of the other, so long as you get the wiring correct. I'd examine the wiring of both sw's VERY carefully before delving into it though.

My turn signal switch works fine, it's just sloppy in function.

I have a 1970 and some of the wires came loose from the solder on my turn signal switch. Can anyone take a picture of the back of the switch and email it to me so I can solder it correctly. Thank you. ricksaia@hotmail.com

Rick, I'm sending you pics from a 73 switch. The wires should all be the same, just the length of the pigtail is different from early ones.

I wasn't reading correctly. At some point they added the intermittent wiper position, and that's the only change I know of. I know at least the '73's had it, '72's I don't know. I hate the slow speed that the idiot off operation where the dam blade stops at the top of it's stroke if you turn it off when it is at that point. I wonder if Nissan ever really tested the wipers, or did they just say "oh we need wipers don't we"?