I am in agreement with what dave.verry said. As a HVAC man I deal with wire connecters all the time and the worst tool you can use would be the very thin crimper/stripper you get at the hardware stores as those do a worse job than just a pair of needle nose pliers in my opinion. The ratchet type are good, I use a set that electricans use they look like a pair of dykes but have several diffrent crimp slots for diffrent sized wires/connectors and are like a 1/4" or more thick instead of those cheap ones that are like 1/8".
Adhesive shrink tape is a must also. Electric tape is a huge no no in the engine area as the heat and fumes will make nothing but an unraveling mess.
Has anyone tryed using the liquid electric tape? I'm curious as to how well/messy it is.