head bolts on 1999 Chevrolet Blazer

When rebuiliding a 4.3 v6 do i need to replace head bolts or use the sameones?

Asked by for the 1999 Chevrolet Blazer
cast iron heads to cast iron block, you can re use the bolts.
aluminum heads to cast iron block, the bolts must be replaced.

you have cast iron heads, so it is ok to re use.

That is what I thought but, I bought new bolts and man you have to strech them petty far to get them tight.