The first change was the removal of the shovel from the front top hull. The other change is the unit's tanks lacked the characteristic side-skirts seen with the Tiger I. The challenge for me was to find an easy way to replicate the hanging studs for the side-skirts (which were present - unlike on the initial Tiger I).
Ultimately I found a source that worked flawlessly. Archer Fine Transfers has a line of surface details. These surface details are resin on very thin, high-quality decal film. Their catalog can be downloaded and has true size scans of the various details. I found a set of rivets that looked to have the right spacing for the studs - granted they're round, not square, but at this scale it is going to be hard to tell the difference.
I drew lines with a straightedge to guide placement of the decal rivets. I ended up using set AR88083 which seemed to have the right spacing for the side skirts.
I cut out the rivets in groups of four cutting the decal with a very sharp hobby knife near the top and bottom of the rivets. I also didn't leave much space at the ends.
Before priming the studs looked a bit large, but after a prime coat they look pretty good. The beauty of the Archer system is it is literally designed to be primed and painted over.
I'm sure they scale out a bit large, but even up close they have the distinctive 4 sets of 4 studs look of the actual Tiger I. They should paint up and weather nicely. I'm still hoping to field this army in late October, and have a LOT of work yet to do... as always!