you are loosing your pump pressure some where, eather in the pump or the gasket under the pump. that dont sound like to much space from the conv. to the flex plate when it is all the way in. i really dont know what your talking about on the pump. if i had a pump problen id put a new pump in. if the pump gears were broke then something broke them, like a loose trans. loose or cracked flex plate or the conv. came apart inside. the pump gears shouldnt brake on their own. didnt you have a viberation in your drive line a while back? if i pulled my trans down and the pump gears was busted id put at least a new pump, conv. and flex plate. if i couldnt see what caused it i think i would go with another trans, conv. and flex plate. ive never had any luck with using shims on a conv.