Getting prepared for an EFI conversion using Ford pieces. For those that have already done this.I would like to hear and see where you cut the hole for the harness to pass through the firewall.
I used the stock fuse box/wiring harness hole(it was square). I used 2 pieces of 16ga plate to guide the hole saw and made it round so the large grommet would fit. If I had it to do again, I would run it out to the right and through the fender apron to mount the PCM on the RH side instead of the left. It's a little cluttered on the LH side. I had also considered running it just under the bend in the trans tunnel so that it was more out of sight.
i ran mine throught the passenger side wheel well when mine was efi and mounted the ecm behind the kick panel like factory
1970 I used a 88 mustang parts from a donner car . I mounted the ECM under the heater/a/c housing with velcro and ran the ECM harness between the a/c heater housing and the firewall. As for the hole thru the firewall just to the right of the non a/c upper heater hose.. I used the factory oval grommet from the mustang harness for the firewall hole . As I remember I used a 1.250'' hole saw and made 2 holes the lenght of the grommet then cut the center out for the gromet to just fit .. Jay
