I'm not really into EFI much as far as the older cars go. However, the caution about hooking the power and ground wires straight to the battery to prevent "interference" from the electrical system has me a little concerned. I spent 25 years or so inside the auto alarm industry. Early (80's) electronic alarms were likewise very susceptible to noise anomalies. Eventually, as more features and more robust processors came about, the alarm manufacturers had to develop better buffering circuitry, allowing hookup in places other than the battery.
I'm not an expert in circuit design, but it seems to me that FAST needs to consult with someone from the alarm biz. Early cars are especially prone to "dirty" charging circuits and whatnot that might still be a problem even with a straight battery hookup.
==============================================
Ford FE Forum:
http://www.network54.com/Forum/74182/
Ford Windsor Forum:
http://www.network54.com/Forum/119417/
Ford Cleveland Forum:
http://www.network54.com/Forum/119419/
Ford Transmission Forum:
http://www.network54.com/Forum/260730/