Ah, haaa...
Right you are, Conjam..sooooo....Mr. Boeing gave us (some of us) a nice VNAV path vector...so, if the approach is 'coded', which they all are, there will be a crossing altitude at the FAF, which, if the aircraft has the feature of VNAV guidance, one can 'cheat' outside the 10 mile fix, because its mathematical.
..or..I could just engage VNAV until 10 miles, then capture the ILS all the while, making a CDA.
To be honest, I'm more apt to doing all of this fun CDA during reasonable weather, anyway.