Yup. As Garand said road wheels are correct. You mistaken models.
This one is mid production delivered in late 43.
Model has some historical inaccuracies, but nothing major really.
There were situations (field refits, or field repair that saw somee wheel removal like here:
even on old cupola variant (early)
But basic tank had 4 wheels in uppermost layer.
Anyway, Tigerology is quite interesting topic of knowledge
with over 1350 built and many surviving up to 1945 from different production batches and with such distinguished recognizable tanks and units, but PSC supplies only stock versions (road wheels are single part)classic with full set of rubber tyred wheels and late with full compartment of late full metal wheels.
As to color, Its not undercoat, Its light grey zimmeritt itself.
When chipped it usually fell off to ground color with light gray edge of raw zimmerit.
But sometimes only upper layer of paste was chipped off. Thats more probably with short time after chippings occurred. Later rest fell off and edges got dirty.
Thats how this looks on bigger scale models when done properly.
(random photo from the net – not mine)
(under the gray chippings lays original factory rotbraun undercoat that i cannot visibly replicate )
You have to remember that paste itself was of similar in color to naked concrete.
