If you do solder, find a drill bit that fits the opening of the jet and rest the jet on the bit. You can get it to a point where you don't fill the whole jet with solder that way. Saves a lot of time drilling, and maintains a bit of the jets true characteristics. Easy to break bits. For air jets, I chuck the jet in a drill and hold the bit with a vise grip. You could do this with fuel jets too, but be careful with what may happen to the jet in the chuck if it spins. I screwed up a few.