I recently ran into odd behavior on my HG and it ended up being a bad 5101 RAM chip. The MPU booted properly, but lamps weren't acting right. Try a NVRAM or a different 5101. Otherwise, it looks like you replaced the IC sockets. Did you verify continuity for all of the address and data lines? Maybe check for short circuits between the pads; it is very easy to create a solder jumper and ohming out all of pins is the only way to check for any inadvertent shorts.