Of the 75 known 429CJ cougars.
Of the production paint colors there is 1 color that no 429CJ cars have been reported. What is that color?
The only other Mercury model that this color was offered on was the 71 Comet.
What is…Competition Blue no wait Competition Green, Yes that is my final answer. 
Steven
No on both accounts - BTW in 71 It is Competition Green Metallic.
See the link below for the 71 Competition green Mustang - LOL Munstang people would call it Grabber Green!
Bright Lime Green
Jeff - You’re correct!
The Top color of existing cars is Black/Bright blue metallic. Last year the first Lt Gold color was discovered. Several colors are 1 of colors. and there are 2 factory special order paint cars.
How many 429 CJ’s were convert.'s in 71, and any in 72?
In '71 there were only 16 C code (Non Ram-Air) 'verts built, 2 standard 'verts and 14 XR-7 'verts. And only 31 J code (Ram Air) 'verts built, 18 standard 'verts and 13 XR-7 'verts according to Cougar By The Numbers. No 429CJ Cougars built in '72. John
I thought they were pretty rare, saw a J code today at a car show, XR-7, white interior, non factory reddish color with darker reddish hood stripe, very nice car.
You saw one but you didn’t get and post the vin and door data code information – for shame 
The Registrar for those rare cars is growling in the corner.
I was taken by surprise, and just didn’t think. My wife and I have gone to 10 car shows this summer, yesterday it was finally worth it, must have been over 300 cars. With this time, only maybe 6 new Shelby’s/Challengers. I’m so tired of walking around like I’m at a new car lot…
Lots of 55,56 Ford Crown Vics. At least 15 Model T’s and the same for Model A’s. Saw my first 69 GT 350 and a 67 GT 350, a 70 Torino 428 CJ Torino Cobra, lots of nice stuff from the 40’s thru 50’s, Caddy Packard, Buick.
Besides, the owner was now where in sight, I spend about 5 min at the car, another show next week, almost the same location, if it’s there, I’ll get the info.
In fact I was more excited about the Full size Mercury fastback roof line , 1967 S-55 with a 428 and A/C, buckets, and with the breakdown according to the Marti report, a ONE of One, with 58,000 miles, a real nice car, just needed the engine bay cleaned up to make it really nice.
Went to 2 car shows today, the 429 CJ was a no show at both places. Did see a real nice set of Cyclones, guy had 2, a fastback 428 CJ and a Formal Roof Cyclone, first one I’ve ever seen, both 1969
Update on the 71 Cougar Conv. 429 CJ, saw it again at a car show, was able to talk to him, it’s a fake, originally a 351. Nice job with the installation of the 429, but sorry to say, no new info for the registry.