727 Trans Fluid Capacity

rally said
I did it like this: engine on dolly(I'm gonna install engine from bottom) mount converter to engine. I then hook the trans to engine, I use the hoist to line up the trans with engine, by that time I turn the crank until the trans complete bolt in the engine, it work.

However after reading your post, I'm kind of worry about the alignment- center line of converter and center line if input shaft. What do you think, should I be okay with it?

I wouldn't do it that way if you paid me. Like Mark said, those splines aren't the easiest thing to get aligned by just slipping the converter in the trans. by hand. Maybe 1 out of a million times you might get lucky enough to be able to do it your way, but I doubt the odds are better than that.