Does anyone know how the bolt pattern, k frame, engine mounts, sump clearnece etc including bonnet clearence is difrent between the single cam six in my AU and the Barra twin cam?
I want to know how hard it is to fit newer engine into AU falchoon.

ford-4l-and-6-cylinder-f1/guide-to-ford-6cyl-updated-weekly-t83794.html

do your self and every one els a favor, click that link, then read every post and bit of information contained in it. The come back and start asking questions.

Essentially it is easy to fit.

Not so easy to get to run whilst maintaining dual vct, but has been done.

http://www.fordmods.com/fordman351-s-twin-cam-engine-conversion-t60016.html