I'm attaching flared FG rocker panels.
I attached the top edge along the door sill and at the fenders and wondering if I should tap screw in the bottom edge as well?
If anyone done this, thanks.

I don't think you should penetrate the floor pan. What I did was drill a hole in the bottom edge of the rocker and attach (are you ready?) a binder clip so I can clip it to the ridge where the floor meets the long. I know it sounds pretty hokey, but it works. I'll try to take a picture tonight.

If my memory is not fuching with me the stock one does secure to the bottem with screws.

Chris,
I had F/G rocker panels on my '70/4 from 1978 thru last year. They were not flared however. I fastened them with small sheetmetal screws where the rocker panel was secured previously with pop rivets on the door sill. I did not fasten them on the bottom, however.Those rocker panels never gave me any problems for almost 20 years.

Correct!

OK.
Also, as I attached the upper edge, the bot pulled away from the body, so it kind of goes straigh down. I have to push it in to attach and I don't know what it normally should be - angled or staright down?

It's angled.

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