What always appealed to me about this bike is the overall Frisco look of it, mixed with that hard-edged New York City style of lane-splitter. You can see that Walt took a lot of his styling cues from Sonny Barger's "Sweet Cocaine" bike, and added his own typically NYC twist on the project. The stance is perfect, and it looks to be charging thru Manhattan traffic just sitting there in the photo.
Speaking of the gas tank, Walt sculpted and extended the steel Sporty tank's tail in fiberglass, then mounted it Frisco style. But, he didn't drop the tunnel or move the filler neck up to increase his gas capacity. He did, however, relocate the petcock to the Lt. rear of the tank. Strange setup.
The other thing I've always noticed on most NYC bikes from the likes of Seigle, SD, Psycho, and Indian Larry, vs. the Frisco bikes, was the use of forward foot controls, over mid pegs/controls. Both the NYC and Frisco styles of bikes developed from a need to cut a fast trip thru heavy traffic and splitting lanes. Just another regional preference, I guess.