sed -E, 131 121 bytes
-10B thanks to @Neil
s/./X&/g
s/X([0-7])/ \1/g
y/89ABCDEF/01234567/
s/[4-7]/X&/g
s/[0-3]/ &/g
s/[2367]/X&/g
s/[0145]/ &/g
y/01234567/ X X X X/
sed
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