Installing the levers is dead simple. Just make sure that any and all return springs or switch plungers go in where they belong - and if your clutch or brake switch has a projecting rod that gets pushed in to activate the switch, be careful around that so that you don't break it off.
The slightly more tricky bit, is ensuring that the brake lever is adequately allowing the master cylinder piston to go out far enough so that the master cylinder's internal vent is working correctly. Heard of cases where crappy aftermarket levers wouldn't let the piston extend far enough to expose that little vent hole. The results weren't pretty. (Uncontrollable front wheel lock-up at speed, resulting in a bike cartwheeling down the track.)
Even this, is not very tricky ... but you have to do it. If you can pry the brake pads back from the brake disk (thus retracting the caliper piston) by at least a millimeter or two, it's good. If the lever feels unusually stiff while riding, or if the brake actuation point seems to be moving outward, STOP NOW (using the *other* brake - not the affected one!), you have a problem.