Not too wide. 7.50 R 16 is a pretty good size. I used to run this size when I had split rims. In modern measurements 255 85R 16 is about as wide as you can go.
Here you go sir:
Plus some yahoo started this thread which might be worth a read:
https://forum.ih8mud.com/threads/split-rims-bias-ply-tires-tubes-and-tube-liners.607335/
I ride pretty skinny tires and I find the steering is better. Plus all the reasons mentioned in the links above.