You're misunderstanding. You can run the fabtech 3.5" basic coilovers OR the OME coils and shocks (the OME system is purchased as separate parts), but you cannot combine the two.
Shocks don't provide lift. The coils in a coilover system provide the lift, while the shocks provide the dampening.
The maximum total suspension lift available for Tacomas, without going with a drop-bracket lift (such as the Fabtech 6", TrailMaster 6", Tuff Country 5", or Pro-Comp 4") is roughly 3.5". While there are many 3" coil spacer suspension lifts available, most lift manufacturers recommend staying closer to 2"-2.5".
Fabtech's claim of 3.5" of lift with their "basic" and "performance" coilovers is simply clever marketing. People like yourself who are new to off-roading or suspension lifts see Fabtech advertise 3.5" of lift and think they are getting a great deal for a bigger lift than other manufacturers. In reality, with 3.5" of coilover lift, your truck's ride and handling will suffer considerably. It will ride very harsh, and you will have very little downtravel left at that height. So basically, if you hit a pothole or similar obstacle, your tire will only be able to drop a short distance (around an inch or two) before bottoming out on the shock. Not only is that a rather uncomfortable feeling (again, very harsh), but it can damage the shock and cause it to fail prematurely, or adversely affect other suspension components.
If you want more than 3" of suspension lift, you'll want to start looking at the drop-bracket kits I mentioned above.