@hughmcc,
opening the older screwless dewalt battery packs is almost impossible,,but her is what i have done,,,,at the top near the pins therre is a friction bolt,,,,i cut that out with two cuts with a hack saw,,, at the bottom i use a dremmel to make a substaatial screwdriver hole to spread the case,,,, same at the shoulder ,,after i repair the batteries i drill out the friction bolt holes reassemble the battery and use some good tape,,not very neat but functional...indianabob grower of fine weeds and a few hosta