You can instead buy some bullet terminals to plug into your existing loom wires and then make up 2 short leads with spade terminals on the end to fit the group a, a slightly more powerful coil, the std cossie coil is crap power wise, use a group a with a some IK27, or AGPR12PP8 plugs and you will notice quite a difference in smoothness(and idle) and low down pull will be better as well, well worth doing imo when I did it.
Make sure you get the + and - right, the markings on the group a coil are buried between the two parallel terminals each side.
tabetha