Changing the strips is not very hard.
The reel assemblies are held in place on the cabinet shelf with a plastic handle snap lock at the front, you just lift up on it to unlock and pull forward, this will disconnect the slide-in elec connector at the rear. Here is a short (kinda shaky) video of a guy removing and replacing an S2000 power supply, it shows how to remove the reels:
https://www.youtube.com/watch?v=9J36Bi4drXYRemove the reel assembly from the machine and set it on a table. Rotate the wheel until you find where the old strip has an overlap where both ends meet. Carefully pry up the end of the strip and remove it from the reel by working your way around the reel. Many times there will be some gummy stick'em adhesive or double-sided tape that holds the strips end to each other. As you do this notice which way the strip is wrapped around the reel so you can install the new one the same way. When handling strip be careful not to scratch them, on either side. Scratches will show up worse when they are in the machine with the lights shining.
Be sure to install the correct strip on each reel, they are not the same. There is a part number at one end of the strip, you can compare that number on your new strip. Generally, the strip part numbers increase as you go from reel #1 (first reel of the left, when facing the machine) to reel #2 then #3.
Here is an explanation on the old NLG website that might give more info:
http://newlifegames.net/nlg/index.php?topic=16878.0