Thanks fellers,
Another member supplied me with a verification thread from another forum stating the 15T's buffer tubes are Mil-spec sized. (At least they were at one time).

Ordered a black, Mil-spec sized ACS-L from MidwayUSA earlier today.

The OE stock on the 'T' just doesn't give me any cheek weld, period.

When I bought the rifle I knew I was eventually gonna change the stock to an ACS but then I found there was a stripped down model with built in QD point, I thunk to myself, I thunk "Self, that's even better!".

And Magpul's rubberized grip is next. I believe I know which size to get on that one.

Thanx again