DRO for square column mill drill

I talked the lab I work in to purchase a Grizzly square column mill drill a few months ago, and have been getting more and more use out of it lately. Given that I'm getting busier and busier lately, I would like to get a DRO for it, but given that I don't get to use it regularly I hesitate to spend a lot of money on it, but time is getting harder and harder to come by so want to find one that's also a simple install. Most DRO's I've come across are made for mill tables that are a little smaller than this one, so I'm interested in any guidance anyone could offer on the topic.