yokev

Yes an alignment IS needed.
Since we're speaking of Auto Spring, go to their site and download the install instructions. It'll tell you right there. You could also call 'Kevin' the owner of A/S and he'll tell you the same thing. It throws your camber off. Your truck tracking straight down the road doesn't mean it isn't out of alignment.
What MIGHT be the point of confusion is whether or not you need aftermarket alignment cams. I can only speak for the A/S 3" spacer, but the answer is NO.
Again, calling Kevin will verify this.
As far as contacting him/Auto Spring:
autospringcorp.com
To answer the questions 'How tall' and 'how much'..? The answer is it depends on your truck.
My rake was 3", a buddy of mine with the same truck but shorter bed had a 2.5" rake, people in this thread are saying they had a 2" rake.
Ford has different struts/springs for the different models/packages throughout the line. There's also multiple tire and wheels choices of varying sizes.
Lastly, even amongst the same model/trim package, you'll find variances in spring tension that result in varying vehicle heights.
As Kevin with A/S put it, 'You can line up 10 brand-new F150 FX4s, and have 10 different vehicle heights'.
Obviously 'how tall' will depend on all this, plus how much you raise your front and what size tires you install afterwards.

RobMann

Google bilstein leveling shocks these are the way to go you get the lift, and better shocks than the factory.

Botrod

Just had my auto spring installed today. I just did the front and I would say it is perfectly level. I will most likely order the rear block so it stays level when I have a load on.

I really like the level look. Now I need bigger tires to fill up the wheel wells.

OhFaSho

may be out of place here but wanted to throw this in because i too read all the levelling kit threads on this site and was concerned i wasn't going to make the right choice. i have a 2013 Fx2 6.2L (like i said may be out of place) and everyone was saying a 2.5" would make me nose high. i went with 2.5" BDS and still have a slight rake and am very happy with my decision...

2013Lariat4X4

Here is a picture of my 2013 with a 2" leveling kit installed. And yes, I did get an alignment. I know it's dirty. For this I apologize . The weather has been horrible. I plan on giving it a good cleaning this week.