I would like to know,"IF":It is possible to,"Change the valve stem seals,on a 1988 Honda Civic,1.6 liter,"WITHOUT" removing the head"?

Please refer me to a source of information which will instruct me as to:How to do that repair.Thank you!. :)

You should be able to.
First, remove the rocker arms and the spark plugs. Now, rotate the engine until # 1 and 4 are on top dead center (TDC). Put shop air pressure into the combustion chamber with a device designed for this. While shop air pressure holds the valves closed, remove the keepers and spring with seats. Replace the seals on #'s 1 and 4. And put everything back.
Next, rotate the engine until # 2 and 3 are on TDC, and repeat the process for these.
Button things up and be careful with your torque. Valve adjustment may be required, so you should inspect lash.

Captain Rich missed one step. You'll need a valve spring compressor to compress the spring so you can pop the keeps off. You'll need the tool to reinstall the keepers as well.

As for sources, you can buy a subscription to Alldata or Eautorepair. But for the most complete instructions, you may want to buy a 3-day ($10) subscription to a Genuine Honda shop manual HONDA

Yes, some special tools, too. I figured if he was in this far, he was all the way in.
Either way, I haven't seen him back here.