For those that remember/care about my 99 Cobra TKO install, one of the install issues was making the speedometer work correctly. This was actually fixed fairly easily by connecting the stock speedo connector to the cruise control output of a pre-99 VSS (connections mesh perfectly). That, in conjunction with the correct settings in my Abbott ERA, made my speedo read correctly. Though not included in the directions that accompany it, the ERA has the ability to make the speedo read correctly, and does not require two units as SHM and some others had said.
The only problem was my cruise control. It would 'hunt' and 'surge' quite a bit. Not a major problem, but certainly annoying. TriBlkCobra (Willie) suggested that their Speed Cal might solve this. He gave me a technical reason, but to be perfectly honest, I forgot what it was.
Anyways, Willie sent me a unit about 2 weeks ago, and I finally got around to installing it last night.
Short story: Problem solved. No more hunting and surging. Additionally, I really liked the install, as there was no cutting and splicing involved. Very clean, and I'm quite happy with it.
I need to restate that this is likely on an issue for those folks with 99 and up Mustangs that install a TKO or 3550. The Abbott worked fine with the T45. However, if you are upgrading the tranny, I'd highly recommend the Dallas Speed Cal vice the Abbott.