This process is also pretty much the same for other kinds of tapes like VHS and VHS-C, D8, etc. The only real difference is the bigger tapes won't require a precision (aka jeweler's) screwdriver. In this case, my employer had some footage mailed to us, and the tape was smashed in the mail. With the protective casing busted, the machine would just spit it back out and not engage the tape head.
What you need:
1.) small screwdriver
2.) original busted tape
3.) new donor tape
4.) pen flashlight
Step 1: Remove Reel From Casing
On this particular case, the tape had no screws to remove and was either tabbed or glued together. I carefully broke the casing apart taking special care not to cause damage to the tape by way of wrinkling, crinking, stretching, poking, handling or otherwise touching the reel. At this point in the second picture I was able to pull out the left part of the reel. With half of the tape removed, getting to the other half was quite a bit easier. When the reel is entirely removed, I suggest winding all the tape to the left reel (thus fully rewinding the tape).
Step 2: Move Reel to the Donor Tape
Step 3: Copy Tape to Permanent Media
In this case, I captured the contents of the tape by playing it start to finish, one time, into my work computer. With the video encoded, I was free to do whatever I needed to with the footage. I checked the captured footage to make sure it included everything I needed, and then gathered everything from both tapes and discarded them. I figured that would keep me from ever accidently using them again. Short and sweet, your work is done. This has been instructable number eight, grab a donut and some orange drink on your way out. Ratings and comments are also highly encouraged.