They will fit fine and look good. Many Duster/Demon/Dart Sport guys run that size tire on 15x7 and 15x8 rims.

1970 FE5 Duster 360/904/3.91's SOLD 1973 TB3 SpaceDuster 340/4spd/4.10's SOLD Moparless for now but when the opportunity is right I'll have another one.