An ILS on the standbys is an annual exercise on the recurrent on one type I fly.
That comment brings back memories of my (long ago now) time on the 737-300. Doing an ILS on the miniscule standby AI, which is waaay the buggery over almost on the centre of the instrument panel and (having just switched to wearing glasses, so having to swing my head rather than just the eyes), including the RMI - the only heading reference - at my left knee, in my scan.
It was do-able, but with a crosswind and a bit of turbulence thrown in, it was... shall we say 'character building' - and a VERY pleasant surprise if the runway lights appeared where they ought to be when you reached the minimum.