I am in the process of fully building one of these but im using the si bottom end, and a 98 vtec head.

So to answer your question yes you can use the EX head.
I would use 96 and up head for the higher compression and better combustion chambers!!!

As far as the ecu you have to use the PM6 out of either 89-91 civic si or 88-91 crx si then send it to Zdyne they already have a program for the mini me fuel, spark, vtec!!!

Also do research you might run into problems with distributor??
If you do a search there is lots of info on these.
Iknow the 92-95 head is a pain in ass to use plus it sucks!!
If you got any questions feel free to pm me.