For general question some info can be found here. Many guys over there know a fair amount about suspension on that year also. I wish I could help but I have a 69 and the set up is totaly different.
http://www.fordmuscle.com/forums/torino-pages/
Dearborn clasics also has some of the interior and rubber parts you need but they are often pricey.
Some advice on engine mods here
http://www.network54.com/Forum/119419/
I know an OAD will bolt up in place of the C6 pretty much with little to no mods. Lentech and a few other companies make good valebodies and fully built AODs to handle a bunch of HP. a freind of mine runs a Mustang with a 351 cleveland and an AOD in the low 11s consistantly, he runs a Lentech valve body.