BTW, Anvart has a similar SH3 mod:
http://www.subsim.com/radioroom/showthread.php?t=118089
When he first posted about it I lacked the skill to understand what he was talking about. My method is different, actually, but his is still very cool.
Actually, Anvart's method will be far better for adding multiple smoke types (coal vs oil vs diesel). When the next S3D is out I will have a crack at it based upon his excellent work.
My technique involved pointing at it with the eqp file. Works, too.
tater