Hi there, I just put this unit in my Cobra II.
It's a 1965 289.
The '77 cobra ignition was ok but I got a deal on the proform for $80 on craigslist, brand new, (only used to check clearance in a '68 Bronco, but it didn't clear the carb.)
However, it did fit the 289 with non-egr edelbrock performer and avenger 570.
I had to drop from 14" to 11" aircleaner though, but thats ok cause the fella also sold me a K&n 11" aircleaner for $10 that was new also.
The proform fired up right away, a little wiggle and it was set.
I notice the car pulls smoother and lights up faster now.
I just put it in about 1 hour ago so I'll have to fiddle with it and check the gear for wear too in a day or two.
if anyone is looking at this, and has a mustang II, the proform works great, the tach works, and I eliminated the ugly old coil and a nest of old temp\oil gauge wires along with the other ignition wires, that were pretty greasy and dangling.
As for chevy product on a ford, I don't mind, it cleaned up my engine bay and weight, it works great and the average human would not notice the difference.
I've got people that think my car is a '67, '73, ect, ect, but its a '77
Also the gas is $1.33 a liter!
I wanna make sure I burn that fuel the best I can so I seen the chance and it worked out.
I've been trying to post here for a few days but my activation screwed up, I was gonna ask what wire to use for my ignition source.
I couldn't wait, so I figured it out after 10-15 trips to the bathroom with my Haynes manual and combing the schematics.
I used the white\light-blue and green\yellow wires off the GREY plug that is before the ignition box.
I just unplugged the grey connector and cut the 2 wires I needed for ignition and tach.
The other end was completely discarded with the un-used endpoints.
Very accurate review, thanks.