I can help you. There is only one special tool that you need, and it is to install the bottom bracket cups. I have that tool. Is there any particular reason why you are going with Ultegra vs Sram Rival or Force? The Sram groups will save you a lot of weight, but if weight is not your concern, then you are OK. Some people also like the Sram for its DoubleTap shifting design and internal cabling. The entire process of switching the group takes about 3-4 hours with tune up.