Hi Ben,
I just quickly measured a 16N that we have here in the shop, the spool width is 26mm. I dont have a regular 16 here in the shop to measure as well unfortunately.
I would be more inclined to fish PE5 over the 16N as you will get around 260-275m of it on there. Any higher and capacity starts to become an issue.
Other options would be something like a Saltiga Z40
If you would like any more information don't hesitate to ask.
Kind Regards
Tom