The notch at the end of the shaft is facing you on the right head, back side of head on left shaft. As far as running synthetic these engines where built before synthetic tolerances, they like regular dino oil and the heavier the happier they are. Your cold oil pressure is below spec, should be a tick under 40psi at 2500 rpm engine at temp.

 

I put her back together. The book says the notch should be up so the oil holes face up. Which oil line the rocker oil ports and the shafts much closer but I cant find much info. I get 40-41 psi warm at 2500. Ima just send it