1969 Pontiac Firebird

Most people (us included) will never get the panel perfectly straight with a hammer and dolly, so a thin coat of filler is necessary. You're going to sand off 95 percent of it anyway, so don't worry about it.

We sanded the filler first with 80-grit paper followed by 220.

Using a block or longboard (as shown here) with 220-grit sandpaper, sand in long strokes to reveal high and low spots. A high spot will show as bare metal, whereas a low spot will be filler or primer.

Fingers are better at finding high and low spots than eyes, so prepare to caress your car a lot. Sanding is the most time-consuming part of the process-we did the fill-sand-feel-repeat routine many times on each panel.

After we were fairly convinced the body was straight, we hosed the car down with gray filler primer, which fills most of the sanding scratches and evens out some very minor low spots. A local automotive paint supply store had this Seymour gray filler primer in a rattle can, which is way more convenient than spraying it from a gun when you're working outside on the patio. After applying the filler primer, wet-sand the car with 400-grit and check for high and low spots. Then do it about 10 more times to get it right.