the front seal you have to pry out of the front pump, around the input shaft of the transmission.
do not remove the cover. it is the front pump assembly
the seal presses into the pump housing there.
get it out any way that you can. punch, screwdriver, hammer, pry bar, anything,
new seal is like 4 bucks and you need to tap it in as straight as you can, a length of pipe the same size of the seal would be the best way but if youre careful you can do it with a medium hammer tapping around it many times more and more until it sits flush into the pump housing
if thats the seal you already replaced then you must mean the big flat seal under the front pump housing.
those normally dont leak or go bad i dont think iver ever seen a bad one, but you can rmeove the pump bolts around it and pull the pump out and it will be ok nothing will fall out
the pump may be stuck pretty good may need a puller/slide hammer to get it unstuck from the transmission case
have fun!