This should help to illustrate Ron's findings. This post was modified much later than the others on this topic, so it may make earlier posts below seem redundant or not make complete sense:
1956 - 1957? (Ads and catalog)
This style first appears in 1956 magazine ads and runs until at least 1957. I have no data whatsoever for 1958, so I can’t verify when this one ends and the next one begins. There is also one with the dual cap/pour spout somewhere in this date range (below - photo by KellyBlues.
[above] 1959? - 1962 (Catalogs and ads)
As far as I can tell, this style first appears in 1959 Outing catalog. It may have come out a year earlier, but I have no proof. It was used until at least 1962 (Coleman Outing Catalog).
[above and below - front and back] 1963
I have no record (catalogs or ads) of this style at all, it seems to me to be a “transition” between the last and the next, so I’m declaring it to be a 1963 only version. The other side of the can is similar to the one above, but not identical. If only I could find a 1963 catalog...
[above] 1964-66 (reference: Coleman catalogs)
There may be minor variations in text arrangement on some of these and the next versions.
[above] 1967-68 (reference: Coleman catalogs)
The heater seems to have been added in 1967, at least according to the catalog. There may be minor variations in text arrangement on some of these. (I don’t have a 1 gallon example of this one yet, but you can see one in OldSoul's post #13 below.)
[above] 1969-73 (reference: Coleman catalogs)
The fixed price no longer showed in the catalog in 1969. There may be minor variations in text arrangement on some of these and the next version. (The one on the left is the one Warren referenced as NOS in the post below this - it's still full!)
[above] In 1974-76, the cap has a white plastic safety wrap, but otherwise seems the same. (Catalog photo)
[above] 1978- (reference: Coleman catalogs)
The cap is a twist and pop type. Note new heater style and silver warning background. (No 1977 catalog available)
[above] 1979 - 82 (reference: Coleman catalogs - catalog photo)
The cap is again the white plastic safety type. Note white warning background. (There are no fuel cans in the 1983 catalog, and I only have one catalog beyond 1983 available)
[above] Unknown date - I suspect it could be just after the one above it, but have no catalogs to compare to. It does have what is probably a 220K, which ended in 1983. The cap is a red plastic safety type.
[above] Mid 1980’s - 1990’s
I have seen this style can in a 1986 Coleman camping video and in the 1990 Coleman catalog. I don’t know anything more.
Here's a newer one, there is a code on the bottom, when compared to the code on new cans makes me think 1992:
1990’s - 2000’s?
The can above is English-only and so is probably older than the one below with multiple languages.
I don’t know the dates on these at all. Maybe some of you have some idea of when they came out?
John - ICCC Petty Bureaucrat #CMLXII...