727?

I thought I read the 904 only came behind the 273 and 318. I could be wrong. also my buddy had a 68 340 GTS dart it had a 727..
Where will the markings be , I'll probaply pull it and go through it. Any suggestions on upgrades to the trans. Going to be similar to stock numbers with a nicer cam and as close to 9:1 as possible.Stainless headers ld340 mani, 650 eldebrock carb. Going to be a nice tight street car. 323,s for gears.