Assemble Hard Drive

My hard drive just kick the bucket last night. I plan to buy a 40GB (5400rpm) 8MB Cache 2.5" Hard Drive for my Inspiron 5100. I notice the pic doesn't really look like my current hard drive so I scrolled down I and saw "Hard drive requires the reuse of your hard drive carrier/caddy, screws, and end pin adapter. This should be installed by a qualified tech, otherwise you can purchase the full hard drive customer assembly kits below for specific models" I have the all the screws caddy,etc from my old hard drive but the only thing that concern me is the button of the hard drive looks a bit different than the one I plan to get. I guess this is where the qualified tech comes in. Is there any step by step instructions i can use to assemble on my own with my old parts or will i have to go to a tech at a hard ware store? thanks in advance