I am not the world's leading expert but I know a little. We are talking Transmission Control Module right? An issue with that will not cause the starter not to turn. Even a problem with the immobilizer will allow it to turn over for a second. I am curious why you changed the TCM. I am going to guess you have a basic problem that may or may not have anything to do with the other work you were doing. So you will need to do some basic troubleshooting. I would first check the battery voltage and the battery connections including the ground.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra