That Gasoline Gus has had me tied up all week. The Gitny bus has been a Octopus on my head for the last Fortnight.

Here’s my take:

I keep getting the feeling that the funny little man in the funny little boat is a reference to Satan’s wife turning to masturbation as her husband, IE, us the listener, the common man and his/our pursuit of the Go-Go “automobile lifestyle” has left her unattended to.

The line about the Tin Coffee mill can be seen to support this if we think of a coffee mill as a another expression commenting on life as being a “Mill” or “tabula Rasa” type device.
In the late 20th century people would sometimes descibe their hectic pace as being like being on a Merry Go Round.

One read for the timeline of when Gus meets Satan good be that When he explodes his bus with the dynamite he is blown up into the air and in the moments before he dies Satan steps in and makes a deal with him to take his Gitny bus or his “dreams of success” and replace them with sexual satisfaction via his wife. Satan knew the outcome all of this before hand.
I think the deal for swapping the bus for the imps was negotiated during Gus’s death sequence in the air. Then afterward he found his “reward” in hell.