The tread come off a rear tire, and it knocked some rust off the wheel well!

I used this product called Great Stuff. It bonds to metal like no other, and is permanent. What I did was clean the area, put mesh down on the inside of the well and then foam it up. Hit it on the inside and quickly on the outside. Shape the area visible quickly because it dries in a couple of minutes. Make sure not to get it on your clothes, skin, or any other place you don't want it, because it is quite permanent. Then when it's dry, sand it down the best you can, and prime and paint it. It's photosensitive. Meaning sunlight will destroy it.
This may not be the answer you were looking for, but it worked on my 242 with the wheel wells hanging by a thread. This fix outlasted the car. Solid too. Only 5 bucks... I recommend it.

If you go that route, it wouldn't hurt to keep a "drain hole" there at the bottom, too. But, keep it clean and dry and POR/Ruststop any new rust spots and you should be fine.

...and for some reason I thought my 245 was rusty. Now I feel MUCH better!!! Thanks!

Had the same severe wheel well rust hole issues in my 240. Spent several summers patching those holes with fresh steel, screws, rivets, and oodles of POR-15. Rust in older bricks is an ongoing battle.
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Mike F - 1984 244 DL - 312,000 miles
Original engine, transmission, drive train, starter
Undergoing reconstructive surgery with POR-15

Either repair the massive structural rust damage throughout the entire car or have it towed to the bone yard. That car is not safe to drive as the frame tube is compromised. If you get rear ended, that spare tire (if it didn't fall out) will be in the back side of your skull. Rust has downgraded the safety of your car below that of a Pinto!

jorrell

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92 245 307K miles, IPD'd to the hilt, 06 XC70, 00 Eclipse custom Turbo setup...currently taking names and kicking reputations!

Wow, what a cautionary tale! Makes me glad I decided to take out all the panels in my wagon when I fixed my sending unit. After fixing the sending unit, I saw this:

I told you that you needed to get new tires.
See what damage can be done with those darn re-treads.
See what they did to the poor Volvo.

How did that duct-tape work in helping keep
the rust puzzled together?

OUCH !