buying my new gears any day now and had a question. in regards to the speedo being off after installing the gears, i spoke with a friend of mine who said that all i need to do is buy the speed cal ($89) device from dallas mustang and install it to fix any problems i may have. is is that simple? i thought it's been discussed here before and someone said i needed to reflash the entire saleen chip for that. which is true? will the speed cal interfere with the saleen cpu? it's a hell of a lot cheaper to buy and install the speed cal than have my cpu reflashed.