Here's some pictures that may clear a few things up:

1.54 inches available space.

1.43 inches available space

crammed to the block route, the hanging Spyder tailpiece. I don't think we can make an individual tailpiece with two anchor screws (required) in this small available space. Not that we don't usually like the tailpiece smashed right against the bridgeblock so the practical space available is about a 1/4 inch less. The bottom center scallop is so near to symmetrical that a symmetrical tailpiece that stays close to the edge will probably look crooked. With just over a tenth of an inch difference between the two sides, I'm afraid that staggered length tailpieces will look more like a mistake. My vote is for the Dragon Wing tailpiece. I think it's the least distracting of any of the choices so far since it echoes the shape of the body and doesn't look like something just stuck on it. But that's just my opinion. The finished tailpiece will have the slope like the bird (when viewed from the edge), the mock up is for footprint only.