This is how the hole looked when I got started.  The tailgate's mostly flat, so I wasn't worried about shaping the plug I'd make.  Before doing any welding, I need to get rid of all the paint around these holes.

The next thing to do then is to make the plug pieces.  I need 2 round pieces.  I used a piece of heavy contruction paper from over at Michael's (see it's good for something!).  Paper like that is good to have around the garage.  I can't reach the hole I'm filling from the back, so my template stunk for size, but I knew it'd be too big so I could make it fit.  If I was just a little luckier, the holesaw I had laying around would have cut the perfect size.. no such luck, they were just a little bit to small.

After drawing the shape on the piece of sheet metal, (I think it's about 16 gauge. Probably a little heavy, but it's what I had...) I cut it out using tin snips.   I had alot of grinding to do to make the plugs fit well.

I think these welding magnets are standard fare if you have a welder.  I've used these so many times to hold a piece when I'm welding.  They worked especially well holding these plugs.  I couldn't hold them any other way, really.  If you don't have any of these, head down to Harbor Freight and get some.  They're really cheap and usually on sale.

Here's where it gets fun.  Well, it's be alot more fun if I didn't suck as a welder. I can still get it done, but I end up spending alot of time grinding once I'm finished.

Make sure you take your time and weld in spots around the piece.  If you hit it all at once, you'll warp the panel.  I put these spots on, then let everything cool for a few minutes.  Before long, it's all welded in.

You don't need much help with this step!  Once it's welded all the way around (that took me about 5 separate times welding) it's time to grind.  Finally, it's all flat and ready for a little body filler.