I am allergic to eggs so I've done lots of research and testing of cakes w/o eggs. There are a couple different things you can do to make cake mixes w/o eggs. You can just leave the egg out and sub a carbonated soda for the water, but this leaves the cake very soft and fragile. Just fine for leaving in pan, but crappy for decorating.
After a lot of playing I've found the method I like best. I add unflavored gelatin and Ener-G-Egg replacer to the oil and soda. You have to be careful to let the gelatin spften a little or it will not mix right.
Unfortunalty I don't have exact measurements as I just kinda guess.
The cake this makes is strong enough to unmold and frost. It's still not super strong so I wouldn't stack it or anything, but it's workable.