Snake -
Regarding cables for your tach and speedo.....
Do you really have a mechanical tach? The last time I saw one of those was on a Formula Ford I once raced about 20 years ago!
As to the speedo cable, how long does it have to be? There are quite a few different cables available - I believe ERA gives the part number for a Mustang unit and it runs out the firewall and then over the bell housing to the right side of the trans to the hook up at the trans. The cable I use has a little extra length even....