The Pugsley has two things working against it. The first, of course, is that some racks don't have clearance for those big, fat tires. The second is that the Pugsley's rear triangle is offset 17mm to the drive side. This lets you run a cassette in the back without the chain rubbing on your tire, but it also either makes your rack sit off-center or requires you to spread the rack's struts to uncomfortable angles. There are solutions. Vik B over the at The Lazy Rando has a breakdown of some of the easiest ways to solve the Pugsley rack puzzle.
I decided to go another way, motivated mostly by my desire to use something I already owned. I had two options at hand: an Jandd Expedition rack and a Topeak Supertourist disc rack. The Supertourist disc has to standoffs that could be trimmed to compensate for the 17mm offset, but has a somewhat short top deck. The Jandd would require no permanent modification and is undeniably burley. So the Jandd gets the nod for now.
Fitting the rack, though, turned out to be a non-event. My first move was to order a new Salsa seatclamp with integrated rack mount. Letting me bolt the mounting hardware up high on the bike avoids some of the awkward angles a rack on the Pugsley would normally need. It also let me set the rack up nice and high, leaving plenty of room for slush and mud clearance with regards to the tire.
The next step was simply to bolt up the rack. The Expedition is already generously wide, so all it took to get into place and compensate for the Pugsley's offset was to bolt it outside of the braze-on on the non-drive side and inside the drive-side braze-on:
You can see that the brake cable runs behind the strut here, keeping it nicely protected.
The same is true for the shift cable on the drive side.
The rack ended up nicely centered
At the end of the day, the end of the day came early. The job was about as simple as it could be, and I'm pretty happy with the results. Soon enough, I'll snap a couple of Ortliebs on here and get to gettin' gone.