Rusted fenders

In the rear fenders there were holes drilled before i got it and now the rust has gone all the way through parts on the rear fenders......

I was thinking about cutting a good piece off a junk yard ex. and welding an all that stuff.....
Some one said clean it up and do it with bondo....I'm not a bondo fan but what say you All!?

 

[X~FACTOR]

Depending on the rust size. If its big then definitely get the piece and weld it in. If its only a size of a quarter, you might get away with just using fiberglass. Either way you are going to use Bondo to make the area smooth.

 

[MONMIX]

Unfortuantely you have no choice to use body filler
( Bondo is a manufacture not a product )
It is difficult to get a clean smooth finish with JUST fiberglass. If done correcty a good quality body filler will out last the vehicle it is on.

Yes, cutting out the old metal and puttting in fresh metal is the best method.

Oh, btw they are called quarter panels.
There is no such thing as a rear fender