dontpanic42: Yip, just cut them off and chuck them away. They're a one-time-use item.
Note: Cut each wire separately so as to avoid short circuiting anything with your pliers/side-cutters.

You should be able to pick a handful up from your local electrical wholesaler. If they won't sell you any, or you can't find any, I'm sure either cyril7 or coffeebaron will be able to help you out.

I also have plenty of scotchloks if you need some. Best to keep the old ones until you confirm everything is working, sometimes you want to check what colours were connected if you get distracted and forget what was what.

Make sure the wires go right to the end inside the joiner and that you can see the crimp has fully pinched through the wires. Dont strip off the insulation from the wires at all, the metal bit inside the scothlok does that for you.