Hi printbus, thanks for the response. I understand about the lack of accuracy when using an IR thermometer to determine actual temperature, but for the measurements I took I clamped the IR above the bed and moved the bed under it, that way at least the angle and distance to the bed stayed the same. I still have the hot end fan exhausting to the back of the printer. In the early stages of warming the irregular heat distribution was noticeable just by touch, so I believe there was an issue with power distribution on the bed. At ABS type temperatures (bed ~110 degrees) where the heater is running quite a bit, ;leaving the bed for 10 minutes or so only slightly improved the heat distribution.

With the additional wiring in place, both the voltage and heat distribution have improved dramatically. I like the idea of covering the bed during warm up, will give that a try.