I'll vote fuel pump is dying. Other issues appear to also be present but in my 15 years and couple hundred thousand miles of experience, the only thing that causes stalling is lack of fuel. There is a Schraeder valve on the fuel rail. Uncap it and (with all due caution) depress the valve slightly. If theres a lot of pressure there, I am wrong. If not much...
...and your car is a GTP, it has a two speed fuel pump. As opposed to a GT which does not. The low speed function is known to usually fail first. However, someone here told me how to alter (bend tab or affix a jumper, don't remember) the relay to sidestep the low speed and run the pump at full speed all the time. That is fine, it works and lasts.
I bought a set of 3 coils in one box at O'Reilly's recently and have not had any trouble with them.
The statement about having had the trans rebuilt to HD confuses me. My understanding is that the HD case is different, to accomodate a slightly beefier differential.
