I put a new alternator on my '89 Civic a couple of months ago and while not trivial, it wasn't too bad. The only real problem was that the bottom bolt had seized and I rounded the nut off trying to get it loose. At that point, I had to bring out the Dremmel tool and cut across it to split it (which basically ruins the nut and bolt). Local Honda dealer had one, so not a big deal.

The only other thing of note, was I had to take the bottom alternator bracket off the engine block to have enough room to take it out the bottom. Didn't want to take the intake manafold off to take it out the top! Jack the car up by the jack point, remove the left front tire which will drop the half axle down enough so that you should be able to wiggle it through.

Hope this helps....