Yeah, pictures please?
Thinking of rims below in 7.5x17, 4x100, ET42 to my vehicle
This is handy and in Finnish,
Tire size calculator
Vanha rengas = Old tire
Uusi rengas = New tire
Nopeusmittarin virhe = Speedo error
Renkaan halkaisija = Diameter of tire
Renkaan ympärysmitta = Tire circumference