MX5 1.8 oil

[Andycarr182]

Hey new to the forum and to my new MX5 MK2 1.8
I did a service and that on it as you do but it seems that I can never get the oil level correct so I don't overfill it. It my Manual it says 3.8 litres so I put in 3.5 to be safe then check it, after I left it over night the level was over maximum, is there something specific to these engines like oil stays in the head for a long time or is it just me 😑