Sorry ass Finnish spare ribs, how long to cook?

I'd cook them for an hour naked, then start sticking a toothpick, or something similar, into the meat until it slides in and out easily. Sorry that I can't state a time, but once you learn it, it gets easier the next time, allowing 15-20 minutes for heat lost while opening the lid to check. It's better to check early and have to wait, than to overcook. This is when alcohol and sides are really important to a cook.
My wife's family comes from your area. She lived there for a short time and says it was lovely. Sisu.

I've was given some racks like these, so I tied them together so they would not dry out, came out pretty good. The side of the ribs that I removed the membrane from faced the outside, the "meaty side" is what I put together. I put a dry rub on before I tied them. Sorry no pictures.

I'd be buying the bone in bellies, I like smoking pork belly.