XFIL owns a salvage yard he had one in his shop it was a series of three horizontal 6" pipes about 10' long connected by two verticle 6" pipes at opposite ends each between two long pipes so it resembled a sine wave laid horizontally air went in the bottom pipe at the opposite end from the verticle.
The exhaust was on the opposite end of the top horizontal from the fuel feed nozzle.
The oil would drip down the top vertical and preheat and burn in the bottom horizontal exhaust went up and was radiated by the entire assembly.
It needed to be started and warmed with another more combustible fuel oily rag whatever was handy
They had to pull the nozzle about twice a month because it would crust over with slag by soot
Hope this helped
The exhaust was on the opposite end of the top horizontal from the fuel feed nozzle.
The oil would drip down the top vertical and preheat and burn in the bottom horizontal exhaust went up and was radiated by the entire assembly.
It needed to be started and warmed with another more combustible fuel oily rag whatever was handy
They had to pull the nozzle about twice a month because it would crust over with slag by soot
Hope this helped