I think all 228s were 4 bolt. The '54 and later 248s were 6 bolt. But according to Hollander, they won't interchange with Chevrolet.

"It's just a phase. He'll grow out of it." Mama, 1964

1956 Chevy 1/2-ton 3100
1953 Chevy 6100 "The Yard dog"
1954 GMC Suburban Now with a new proud owner.