I am not 100% on this, but I think as long as you pledge $1 (because you don't have to select a reward level) you will get a link to the pledge manager after the KS ends and can then add stuff a la carte as you like. Check the updates and comments on the ks page to see if someone has asked that question maybe.
Although, going by the retail price point of the SDE FK game at $100, if you want the base game box (assuming it will be about the same price) then it won't work in your favor to do that.
Also, not sure when this happened, but it looks like there are now 3 options at the $100 pledge instead of 1.
Last edited by morella888; 03-25-2015 at 12:12 PM.