there are a number of ways to go to fuel inject your mustang. i recommend using the hardware, the intake, injectors, fuel rails, etc. from any of the injected 5.0 ford engines. then use a megasquirt fuel controller. check out these sites;
It should be a lot easier and cheaper just to fix your choke. Your car should start right up and go after about a minute. If not then your carb needs attention, that's all. I usually let my cars warm up a few minutes on really cold mornings though, EFI or not.
Of course if you just WANT to swap over to EFI, then that's different.