go for a d15b vtech or carb , vtech will cost more..
as for fitting youll have to change 2 mounts , other mount (back) is compatible with the d15b , well that was for my case in my 84 ballade , i dont know if 86 civic has the same specs of engine mounts. but its My Very Strong suggestion Dont compromise in engine fitting bro in any way , get if fitted to perfection, if you even ignore a little part later on huge problems can arise out of it and always take some one experienced with you / speaks pushto or goto to some place whom you know. I had bad experience with my swap and afterwards paid for it