Years ago I had a "Dirty Dozen" in a 72 Kenworth conventional. It was great fun then (I was younger) and fuel was cheap!
I can't vouch for them living a long time though, since I had to rebuild mine twice in the six years I had it. Once in-frame and once out of frame complete overhaul.
The second time around, I put in a set of matched, high performance, modified injectors. What a blast! When we put it on the dyno, it put just over 500 hp to the ground!
I could pass anything on the road except a fuel station. If I was using the power (and of course I always was!), I would get as low as 3.5 mpg!
And those are Canadian gallons too.
Also I could mention that I had dual 5" straight pipes on it! Could be the reason why people have to yell at me all the time now. lol
Later. . .