AFAIK, Swift uses the industry-standard 6 1/2" mounts. Unfortunately, I'm not much of a fan of Tangband midbass. If you can find yourself some Silver Flutes or Peerless SLS, that'll be great. I'm also quite fond of Dynavox (
Dynavox LW6004PMR 6-1/2" Woofer).
Rather than a normal tweeter, I would recommend you go for the full-range plus midbass combo to save up on fabrication costs. Something like a 2" Vifa (
Vifa NE65W-04 2" Full Range Woofer) enclosed in a DIY tennis ball enclosure crossed at 800hz upwards would be great if you plan on mounting it on the dash. Or better yet, throw them on the sails. You want them on-axis as much as possible.
Now, the next problem will be the head unit.