Alum headed 408 running hot come in....

My 410 SBM runs at 170- 185* no thermostat and straight water. Aluminum Radiator , mechanical Viscious Fan & No Shroud with Iron heads. I live pretty close to you so it should be a good comparison. My initial timing is 24* and 34* all in, no vac advance. Sounds to me like it may be running fat and that could be part of the problem, does it smell like raw fuel?check your plugs. They may be on the way out.