"Long tail fin, taillight half filled-in, one nose filled-in"
The distinguishing features of this version include a filled-in right nostril on the bat nose and taillights that are half-filled in, longer tail fin tips.
I'm guessing on the year this version appeared. This version represents the first change to the actual body molding. That this is not a very common version. At first, it appears identical to the 1966 version (bat hubs, pulsating exhaust, etc.), but the body molding was changed in the area of the bat nose and tail lights. The more obvious change is that the recess for the tail lights was not as deep as before (but it also was not filled in completely as it was in the next version). Less obvious is the fact that the right "nostril" was filled in although the left nostril was still recessed. No doubt this was a mistake and probably explains why this version is not that common. This version is often mistakenly passed off as a "1966" or "first issue" and it seems like folks always want to display this on a fold out box. But, in reality, this is not a first issue.
The Batmobile never had long tips with both nostrils filled in and both taillights filled in with Long tips, it only ever had short tips with both nostrils and both taillights filled. They changed the moulds to accomodate the changes to the wheels. and adjusted these at the same time. Body changes before were temporary ones without changing the mould, they tried to adjust it instead before. They tried to modify the existing mould instead of replacing it. The no towhook Batmobile only appeared in 1966, but was still available in shops a couple of years after this. Very few of thiese had a nostril filled in!! The towhook version then had taillights recessed and one nostril filled in, when both noses should have been filled in, and you will find some with no noses filled in but with taillights recessed. These were all simply moulding errors that occurred over the 5 years until the mould was replaced. Its like with the passenger door filled in part, something just simply got stuck in the mould and wasn't noticed. It could happen any number of times, especially with the nose as it was hardly noticeable on the mould. I couldn't give you an idea on the figures though, But my guess would be that its rarer to find a Batmobile with a towhook with no noses filled in, but thats a complete guess due to the amount of errors that did occur with this 1967-72 model. The short tips though with the taillights filled in and both noses is the rarest of the bat-hubcap models.
None of these no towhook had the taillights filled in, but did have them recessed. Very few would have done though, maybe as low as 50, not more than 100.