Not a good idea. Plastic filler is too fragile for something like this and will easily chip or even worse, a big chuck could be knocked out by a very slight hit.

The edges of an auto body must be metal. At the very least I'd grind the filler out and use lead or better yet remove and re-fit the new part to the proper clearance. That's where the weatherstripping goes and if the contour of the contact surface isn't right the weatherstripping will not seal properly or bind so tight the door may not close.

It's always a good idea to bounce these things off this group before making radical decisions like this one.

Woody
Your Brother in Bolthood

My 1951 half-ton 'Ol Red

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