I haven't installed a DRO on my 10" Wards lathe yet, but I have done a small amount of research. There may be differences between the 9" and 10" Logan lathes that I'm not aware of, so take this for what it's worth.
To me, it seems like the biggest challenge to installing DRO's on these machines is the cross slide. Mounting a scale, especially a glass scale, on the right side of the cross slide would greatly compromise your ability to get the saddle close to the tailstock. Given the limited travel of the tailstock ram on these machines, this becomes a real problem. Mounting the scale on the left side of the cross slide might be an option, but you may have the same issue with not being able to get it close enough to the headstock. The significance of this issue may vary according to how far your chuck sticks out, or if you are using collets, etc. Also, with the scale mounted in this position, all of the chips will be falling directly on top of it, so guarding is especially important.
The best solution I have seen so far is to mount a magnetic scale directly over the cross slide lead screw and underneath the existing cover. The read head is mounted to the back end of the saddle. I first saw this on a YouTube video - I don't remember the author, but I'll see if I can find it.
The Blu-DRO setup with the magnetic scales gets a lot of good reviews:
http://blu-dro.com/
That's about all I know. I'll be looking forward to hearing others' thoughts and experiences.