I am also running the 1976 Blazer 15"x8" Ralley wheels under my 55 Cameo, but I am also using the 4x4 axles. I am in the process of re-installing the original front and rear axles but will keep the wheels, as I am planning to run disks on all four corners.
Bob


55 Cameo 396 TH 400 with overdrive
65 Caliente conv
67 BB Caliente conv
67 Mercury 1 Ton
76 GMC 3/4 ton 454ci
84 Buick Turbo Regal