IMO, it should have FIND systems, when trains are switched from route to route along the 2,4,5 and 6 lines, the strip maps aren't changed out, best to have the LED display so that it could be displayed properly
Like the R143 sets, which were made specifically for the BMT Canarsie Line (even though a set or two was on the (M) before CBTC went live on the (L) train), The R188 sets (including the R142A conversions) are specifically made to run on the (7), and to use CBTC once it goes live on that line.
The fact that both the BMT Canarsie Line and the IRT Flushing Line are both non-shuttle, self-contained routes (Meaning hosting a single service) explains CBTC operation the (L), and the current conversion to CBTC operation on the (7).
Either way, as you know, the IRT Mainlines run 10-car trains, whereas the IRT Flushing Line runs 11-car trains.