Okay, I have done this many times before but the last time I tried to do it I failed miserably and had to call a plumber. I know this is simple but last time I could NOT pull that darned cartridge out of the pipe after I took the handle off. I know to remove that retaining pin 'thingy' and grab a bit of the cartridge and pull it out. It would not come out. I ended up putting it all back together and calling a plumber, who also had a heck of a time getting it out. So, now my bathtub faucet has a drip again and I want to replace that cartridge. Oh, let me say it's an older single handled Moen bathtub faucet. Is there any special tools I need that I didn't have last time that might make this go easier? What I do is use a screwdriver to remove the handle then I use pliers to grab a bit of the old cartridge and try to pull it straight out. Is there anything I should know here that I am missing. Also, I have bought a generic cartridge. Would I be best served to return that and buy an actual Moen brand cartridge? I would appreciate any suggestions or ideas. I want this to go as smooth as possible and I am going into this very simple project with a little trepidation. I am 'older' and a 'girl' so home repair projects are not my forte, really. But I do what I can.