No ported head, why use a good kit like the APE kit or any other with similar components? Smaller chamber job and port clean-up as Hondaman recommends is much better than nothing.
Check options with MRieck.
Ported head is a mandatory part for me when upgrading the CB750 with higher CR pistons and cam. Most old heads out there need most likely a valve job recut seats and lap valves, maybe a few new guides too.
Lighten the alternator is another low cost upgrade.
Look for a used ported head.
My last K2 build got new stock size pistons and head with refurbished seats.