Roller rocker ideas for 340 build

Right now it is looking like I will be doing a complete roller setup now. I will more than likely just save for the whole setup and do it right the first time. I have a few questions though about this though. 1) 1970Duster I know you always preach to run a roller cam with the cast iron gear. Right now I am planning on running the Comp XR286HR-10 (286 intake, 294 duration and 236/242 @.050 with .544 lift), which has the steel gear. I do plan to switch the dizzy gear to the Comp 420 bronze gear. Will that work too? 2) My 340 block has various depth chamfers in the lifter bores. Will this effect oiling for the roller lifters? This seems to be the hot debate regarding roller cams not getting sufficient oil to the rockers due to losing pressure at the chamfers.