EBS: alternative to port pools

I have a customer cloning EBS who is apparently not using port pools during the cloning process.  As background, since EBS uses dozens of network ports when deployed, "port pools" are offsets from the default port numbers that each cloned instance can use.  For example, the default TNS Listener port is 1521, so employing port pool "15" means that the TNS listener will use port 1536, and all other EBS ports will be offset similarly.

Is there another (documented) method for assigning ports, perhaps by editing a configuration file and then re-running "autocfg.pl" perhaps?  Or that strictly verboten?

Thanks!