Two Temp Smoked Ribs?

If you are wrapping the SLC ribs, no need to keep the same temp other than time control. 

If you are not wrapping, upping the temp would just finish them faster.  Don't think it would do anything to the outside unless you let them go too long.  I don't wrap my spares, and I only lightly dust them, so I don't consider the outside of my ribs barked, not like a brisket or butt.  The outside is a little firmer than the tender middle, but it is a long way from bark.  

We sauce a lot of the time, but occasionally I'm in the mood for a dry rib.