When looking into the converter, the larger first set of splines is the stator, the smaller second set of splines is the turbine; a non-lockup will have what looks like a flat bulkhead past the turbine splines, a lockup will have an additional bore with a bushing past the turbine splines.

If the converter has a drain plug it isn't lockup, if it's a 12" converter it isn't lockup.