Jobmate cordless screwdriver

Hey guys!!! Long time no see, I have been busy doing other things in my life and coming to check on here completely slipped my mind, I feel so bad now after seeing how many comments I've missed out on replying on. Also, I noticed some people around here have a PRO beside their name, what is that about? Anyways I have a question I wanted to ask. I bought this handy little cordless screwdriver at a yard sale yesturday, and got it home, plugged it in to charge, and it seemed to be holding a good charge, I used it to change some tweeters in my tower speakers, it has good torque, and good speed. Overall, for $1 I was happy with my find while out on my little adventures. Well, I went to use it this afternoon, and it was dead :( Apparently the Ni-Cads are toast. The problem here is, theres only one screw in the side of the unit, and it only lets me pry half of it open, I can't get the top off of it, there seems to be two metal tubes holding the top on. Does anyone have any idea how I'd pop this thing open?? I want to see about replacing the two cells inside with some rechargeable energizer AA's I have, would I not be able to charge them with the built in charger?? They are NiMh however..

Picture of Jobmate cordless screwdriver
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