MTH Imperial S2 Turbine: Will it fit?

We apparently have the same collection 

I have the three engines you reference.  I run O-60 curves outside a loop of O54 connected with cross overs.  My big concern was running it on the inside loop and having it swing out and punt the outside train off the rails.  So far, my fears have been unfounded.  My S2 doesn't behave that differently than my M1a;  both can travel the inner loop without encroaching on the outer loop.  Even on O-48 curves, the over-swing isn't too pronounced.  I compare this to my RK Allegheny which really swings out to the point where IMO it looks almost absurd on anything less than O-60.   That thing would almost certainly hit your scenery.  

No guarantees;  I'll try to get a crude measurement this evening after work.  My gut tells you you'll be OK.   You'll like the engine if you get it - but be warned that it is a smoke machine.  No chuffs means it just belches smoke as soon as it fires up.   I like that sort of thing 

I look forward to what you find out.  The track I have is Atlas.  It might be more accurate (if possible) to measure from the center rail out, as I suspect that different track manufacturers may have ties of varying lengths.

I have an Imperial Big Boy, there is some tail swing of 3" on my 036 track.

Dan