Chris,I'm another advocate of butt welds.

I attempted this repair on mine and as a complete novice I am more than happy with the outcome.
I've always considered lap joints as moisture traps.
I also have no qualms about using a small amount of bondo,purely to tidy up the weld seams,rather than carving the panel to shape.

We would all love to have the ability to metal finish,but I personally do not have the time or patience to attempt this.

I had a VW Bug a few years back and the PO repaired the rear 1/4 panels with lap joints, the repairs didn't last well.

1950 Chevy Advance Design 3100 in Scotland
In the Stovebolt Gallery
More pix on Flickr.
I've definately got this truck thing in my blood ... my DNA sequence has torque settings
"Of all the small nations of this earth,perhaps only the ancient Greeks surpass the Scots in their contribution to mankind" Winston Churchill.