There where two sorts of these field painted (Malta)Spits:
a.the version applied on US Carriers paintshops using an unknown ANA/USN colour.
This is the evidently darker colour in appearance, solid at first glance, but
soon enough this US colour chipped off in the salty, corrosive, fumes, heavilly rugged areas
like it has partially never seen an additional paint before.
b. Malta field paint application of an unknown blue-grey mixed up from stocks.
Distinguishing by it's overall less darker, less solid appearance, even when freshly applied it
looked like fainted, partially densly applied, possible due to shortages,
using thinner or other attempts to stretch the paint. Application was known to
be down with everything spanning from spraying, brushing or old clothes...
In both variants of additional overspray Undersides where left out as they were,

or some had lower demarcation line at Vokes Filter, the only distinguishing difference,
there was no standard for that.

Your Screenshots reffer to what I described under b., relatively fresh in appearance, it looked like this
the first couple days. As soon as it entered constant Malta service, the overspray cedes to exist at parts of the nose,
wingwalk sections, partially on the fuselage too, as pilots tored off the paint while climbing in. Constant UV glazing, Salty humid sea, sand, dirt, oil,
mechanical affects. The only roofed shelter they might have seen cramped under a carriers deck while on transfer, afterwards they
were exposed to whatever is bad for aviation paintcoats and a Spitfire.
There are top-notch Blank/Generic Skins from the past, by Kristorf or others that might suit your needs. Check all Skins at M4T or Asizbiz site.
Kind regards
Tobias