no such thing as an 8" cop wheel....the only 8" wheels mopar made were the super coupe wheels (look like cop wheels but without the nubs for the poverty caps) or the ramcharger wheels. IIRC both were in the 3.75" BS range.
a 7" wide wheel will be 8" outside to outside. it's 7" from bead seat to bead seat. an 8" wheel will be 9" outside to outside. sounds like you have 15x7's and 15x6's to me. for the 15x7's a good size tire are 255/60R15's.
1976 Spinnaker White Plymouth Duster, /6 A833OD
1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!***
2011 Toxic Orange Dodge Charger R/T
2017 Grand Cherokee Overland
2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)
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