318 Build - Expert Review Needed

The “what I would do” response:

Have the heads machined for 1.88 intake valves and pay someone who knows what they’re doing blend that into the bowl, and mildly relieve the chamber around the the intake valve.
This would be no more than 1cc worth of material removal.

I'd do this in a nano second and add 1.6 exhaust valves, very much worth time and money........for valves, get used take outs, might be able to get them for free