It really depends on the type of shoulder injury(ies) that you're dealing with. For me, I flare my elbows out and take a medium/wide grip. Oddly enough, it hurts less than elbows tucked.
That being said, if you watch me bench, the weight I use is not heavy at all, I use full ROM, and my tempo is something like 3/2. The best thing I ever did for my bench and shoulders was increasing my shoulder and chest flexibility. In fact, not only did that help my bench, but it helped all my pressing. I can bet that the two biggest reasons for bench injuries is too much weigh and/or should flexibility, which effects your form.
Now, let's say if my shoulders were giving me trouble a particular day, there is a seated chest press machine that seems to be easier on my shoulders too. Years ago I had asked Shelby Starnes if he thought using the machine was going to hinder my progress, and his reply was blunt; if you're able to push yourself, pain free, then you're NOT hindering your progress than if you tried to go super light and use half reps on BB bench.