Ok, Im going to try to explain this in detail.

My quarters were rusted pretty bad. On driver side-rusted mostly externally, on the passenger side you could actually see through the cancered wheel well. So...

1. I grinded out as much of the rust from the wheel wells as possible(with a metal grinder).
2. Replaced the area with pre-bent sheet metal (to reform the wheel wells).
3. Drilled holes through remaining 1/4 panel, through the sheet metal. (with a small size drill bit)
4. Loaded the rivet gun with the rivet, put the rivet through the drilled hole, and popped the rivet in (by squeezing the handle), this now securely attached the sheet metal to the 1/4 panel.
5. Grinded down the tacks to make surface smooth for bondo.
6. Sanded, then bondo, the sanded lightly, then primer sealer.

I used the Zinc rich primer, a buddy of mine told be that that was the best for the particular "temporary" restore.

The hard part really wasnt the acutal replacing the 1/4, the hardest part was fabricating the sheet metal to reform the wheel well area I had grinded away.

[*Attached are pictures I googled of almost exactly what I used for the job. The 1st picture is the tack gun, the 2nd the rivets themselves.*]

Now remember this is backyard body work, and by all means is nothing but a temporary fix. Depending of the preciseness and neatness, will determine how long it will last. Primer, and paint+clearcoat probably would be the best steps to take after all the work is done.

Pictures of your 1/4's might help me help you. If you need pics of how mine are now, I think I could hanlde that also.
Hope this helps more.