Rusty rear arch repair

[Harro]

Hello there,

 

Not sure what I'm thinking is a repair or a bit of a botch, but gonna try something.

 

This is the rear arch after been parked up for a while.

 

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Not good, so took bumper off to see how far rust has gone.

 

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Not good underneath, couple of holes. Here's after some cleaning.

 

 

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What kind of treatment is recommended?

 

Rust stopper stuff, filler, blather in underseal?

 

Any advice appreciated.

[gillywig2]

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