Re: SY/TY ECM Chip
www.moates.net. There's a g1 + 512 chip combo. That's all you need.
(Assuming you have the chip burner, obviously. A wide band o2 is pretty much a must also, if you intend on doing anything useful.)
If you think you're just gonna download a file from someplace, burn it, and have everything be right, you've got a long road ahead of you. A good tune is a rather long, drawn out process, not just a one-shot-and-you're- done kinda thing.
Read the tuning threads here and the stuff on code59.org.