I asked a few times and never got an answer to this question so after some tooling around I thought I would post this here in case someone else needed to know!
--------------------FOR X, Y, Z, ADJUSTMENTS OF SMOKE AND AFTERBURNERS IN FSX-------------------------
(It took A LOT of playing around to get this figured out!)
the first is forward & backwards
the second is left & right
the third is up & down
ex.: smoke.0= 1st, 2nd, 3rd , fx_eng_exhaust_gry
Hope this helps!