Rough idle issue

The Oregon 2106 cam is the Dutra RV10 (vs. the 2106R, which is the RV10-RDP). It's an optimised version of the MP 243 cam (which was 244°/244°/28°/0.436"). Nowhere near a big enough cam to cause rough idle; there's something the matter here and I'm guessing it'll be found in the carburetion department, but you might try backing off your valve adjustments to 0.020"/0.020" (hot and running per valve adjustment procedure) and see if it does anything for your rough idle. If not, it's easy enough to change back.

15° BTDC is a lot of initial timing—could easily be too much. Some time and effort or money invested in dialling-in your advance curves so everything's happy at 5° to 7° BTDC will pay back handsomely. Talk to DusterIdiot over on slantsix.org if you're not up for recurving you distributor on your own.