Good thread as I've thought about adding DRO's to my 9A and Heavy 10, but the cross slide designs don't make it easy. I don't think it's in the cards on my 9A as I have alternate cross slides and I don't want to have to move the scale around when I swap them out. My Heavy 10 has a taper attachment, further complicating the issues. I think for both I would only add DRO to the beds and stick with the dial for the cross slides, or just keep running the bed mounted indicators. I've also thought about making an indicator bracket that could quickly attach to the front of the apron with a 2" travel indicator for those times I'm tired of counting cross slide rotations.
On other lathe's I've done similar to yours adding it to the TS side. One thing you can do to keep the TS from hitting it is drill and tap a bolt into the base of the TS and adjust it so it projects out under or beside the reader head enough that it contacts the carriage and not the scale or reader head when the two get too close. I've had plenty of times setting up a job with a center in the TS that I didn't give myself enough room and ran the carriage into the TS, or was sliding the TS in to place and hit the carriage.