I agree with Sunray, the correct tools make it a fairly easy job.
i bought a bench belt sander to do pads, i do enough the 100 bucks was worth it just for that.
Also a pad sanding jig is worth the money it makes life quicker and easier.
For the best fit, you still you still need to sand it in on the stock.
When doing a pad now i usually wait till im gonna do a refinish then sand them im together to produce as little seam as possible. You can use a layer of tape to keep from scratching the finish if your not refinishing tho.
If youve got the tools, Watch some of the video guides, see if its something you think you can tackle. Ill be honest i probably ruined the first 2 or 3 i tried to do.