It may be possible. It surely appears that the two radiused slots (180 degrees apart) on the balancer are there for pump bolt access.

As I said, I didn't even try that. It turned out that removal of the pulley & balancer were fairly easy. In addition, I didn't want to turn the crank, as I had marked the relative attitude of the distributor rotor button.

With regard to radiator and fan shroud removal, I did so after checking prices of a replacement radiator, should a wrench launch itself in the wrong direction ;-), and to create additional working space.