Yeah, if you've actually done all the wire soldering (all the yellow wires in this image
in the tutorial), then you'll need to desolder those wires. You should probably also desolder the 2 5-pin headers that those yellow wires were hooked up into, snip them down to 3 pins each, and then put them back in in a 3x2 pattern, and then figure out which pins on the new programmer header go to which pins on the IC (see this image
from the other thread). and solder them all back in appropriately.
If you need to do this, don't be bummed! I had to do it a few days ago, and it was a great noob learning experience (how to desolder, thinking about which wires go where without just following the directions, etc.)