Welcome to the forum. When you get the kits playing together or even before...... we like pics.
A slow introduction means a week or more to introduce cats properly. You need to do the whole separation, smell, exchanging sleeping beds, etc..
The best advice I can give you is to start over and separate the cats. This is a great site to read for information. The woman has a housefull of kitties and has learned over the years how to do it right.
http://www.squidoo.com/multi-cat-management
Good luck and again, welcome!