Here I am reviving an old thread...one I started...for two reasons.
First I have an answer to the question. What is/was a Guerciotti Jet. Answer below:
Second. I now own the frame again. It came up as a SS on local Craigs and I offered to buy it back for what I sold it. Buyer accepted. So it is now in the basement getting a bath to remove all the grunge. Should be a fun project.