I wouldn't mess with the drive yourself if the data on it is seriously mission critical or very important. You need microscopes and dyes to align the servos on platters if they have been removed. I am pretty sure these tools are expensive and you need a clean room as well so you dont get any dust or hair on the platter as well. I have had drives crash on me all the time and I won't touch them myself. Call some data recovery company to do the job for you. I have used several of them but as far as I know there is only one near where I live. http://www.renewdata.com they have recovered critical stuff for me before.
Hope that helps.
