100-4 BN2 Front Fender with extra Groove

[mwagon]

I started stripping the paint off my front fender & realized there was a ~3/8" groove that had been filled in with bondo. Groove starts by the Fender Spear & follows down beside the rear side of the wheel well opening. Similar to the path of the 6 cyl. fender ridge. I contacted Roger Momment to see what knowledge he had. Roger had run across this before & his best conclusion was that the factory made a few of these fenders near the end of the BN2 production, possibly testing the looks for the up end coming 6 cyl. cars. Roger ran into 4 of these fenders in the 90's from a dealer stock, that had the groove filled in.
Because of the fenders uniqueness & doesn't look too bad either, I was thinking of leaving the groove exposed for my restoration. Does anyone else have any knowledge of these grooved fenders? I'n not sure how to ad a photo from this site to a post

 

[Brinkerhoff]

I don't think the factory would have used bondo however , they would've used lead if yours are originals. I could be mistaken

 

[richch]

This was an exercise the factory tried to try to stiffen up the almost totally flat area and prevent the panel from oil canning when a knee presses against it. They were originally pressed and then lead loaded so they'd disappear. They were NOT meant to be seen on the finished car.