that 93 is a fuel injected motor, unfortunatly for you your carbed right now. To put the 93 in you'll first have to switch over to fuel injection. This is going to require you scoring the entire fuel system (tank, pump, ALL of the lines, etc.) from a Si (fuel injected) civic of your vintage. This is due to the fact that the carbies are a low pressure system while the Si's sport a high pressure system.
Once you have the fuel system swapped your going to need to rewire as the 93 is OBD-I and your 87 doesn't even know what OBD stands for, you'll most certainly need the ECU that came with the 93.
As far as it bolting in, they are both D-series motors, so it may be a simple bolt in, but I am not really sure.
You should definitely take a look at redpepperracing.com since you've got the 87, everybody there is 1G CRXs and 3G civics (i.e. you) and are very knowledgeable about the cars.
Hope some of this helped.