What year did S&W widen J frame rear sights?

[20nickels]

I'm on the hunt for a lightweight S&W J frame, but I want the wider ditch. What year did they start doing that and is it model specific, or the whole J lineup?

 

[20nickels]

Maybe I can make this thread less boring in order to attarct replies. What Is the World's Biggest Handgun? Linky;
http://www.spike.com/group/manswers?video=3025894&epIndex=1&viewOption=images

 

[rcmodel]

They changed the Model 36 & 37 Airweight from 1/10" to 1/8" in 1990
with the 36-7 & 37-2.

As for the hodge-podge of recent guns, I haven't got time to look them all up.

rc