I haven't ran that bore size but I have seen witness marks on my heads with .035 P to head clearances and not with .040 clearances
Those were a set of Ross custom race pistons with around .0080 piston to cylinder wall clearances on my old pump gas stroker motor, those witness marks were on the cam side and motor mount side only so they were close when firing when they reversed directions with combustion pressure on them
I'm of the opinion that with the street alloy you can run them a tiny bit closer than with the looser race alloy
Your choice on this