Compression release?? Never seen one and I know Pablo was looking for one for his ride. I had that under bar tank that I bought from Dax and never could get it in a frame that it was cutting the petcock and carb so tight. Ive tried it on mainly 27 inch frames and just didnt like the setup. Now its up to Joe to try out. I bought it for a antique that I wanted to copy and was going to skin some 18 gauge sheet metal over it to copy the old tank but just never got to what I wanted.
Looks good though like to see more pic of your bike and that release you were talking about.
Terry