This is a fairly simple re-wiring mod. I did this on my DeForest Crosley Model 870 (Rogers Chassis 8M-721) as a stop-gap until I found another 2X3 (I only had one) – see my posting on this set under ‘Show and Tell’. I share Phils puzzlement as to why Rogers ever used two half wave rectifier tubes to act as a full wave rectifier (they did in many of their sets in this period – well after the widespread use of dual rectifier tubes). Like Phil, I can only think of cynical reasons like more tube sales and ‘tube count boasting rights’ by Rogers marketing folks. Anyone have a good technical reason?