I was going through the Legendary website looking for a vinyl roof for my '69 GTS. And I find they list both a 43" center deck and a 38" center deck. Which one is correct? There are no remnants of the original vinyl roof so I can't just go out and measure the old one.

My '69 Dart GTS 440 M-code vinyl roof has been removed but on one side it is still visible where the "seam" was located. The width of the GTS's roof at the front of the door up from the point of the vent window is 50" across. The visible "seam" line is 6 inches inboard of the edge of the roof on both sides or 12".

50" - 12" = 38" on my '69 GTS. If the "center deck" is the space between the two "seams" then mine is 38". Hope this helps.

You might be able to use these photos as reference points to measure on your GTS to get an idea??

The last photo looks like the "seam" would be the 43" center deck as it appears to be less than my GTS and less than the other three photos I posted??

Not that it matters, but the wider seam spacing in those photos looks better-proportioned to me.
I've owned a '69 and a '73 with VT but can't recall the seam spacing very well decades later.

I wonder if it is LA VS. Hamtramck production

Thank you, thank you, thank you!!!! I appreciate the photos and dimensions as they nail down the situation. As to which was correct, it seems the answer is that they both could be. 6bblgt's comment about the assembly plant is intriguing. Unless something else more definitive is unearthed, I think I'll go with the 43".

My original paint 69, 340 la built swinger is I believe 43. I would have to measure it again, left that part on the car.
As I’m in process of restoring it. So I would know what to order when time comes. All original car
Update
I just measured it, most definitely 38”. Hope this helps someone.

Looks like 38" with the distance of the "seam" from the edge of the roof. Compare yours to the green Darts above. The T7 or bronze Dart 440 looks to be the 43" center between the seams. But it will be great for you to measure yours

I always used the 38" seam. I do have a couple of Western Sport Special's but don't remember if there is anything left of the vinyl tops, they are both parts cars...