Take the head to a auto machine shop and have them magnaflux it and check for warpage. Then might talk you into replacing the valve guides and cleaning the head, both are also good ideas. If you do get it cleaned and new valve guides installed, take him both heads.
Haynes manual will work for this repair. There are better service manuals, however the Haynes manual will work.
While you have the head(s) off, notice how clean or dirty the pistons are, clena them up some. Keep them covered so the walls don't rust. Srapy them with oil (WD-40) so nothing rusts.
This is what my sons 4 banger engine looked like after I pulled th head off. He also blew a head gasket. Cost me $80 at the machine shop to have it magnaflux, cleaned, and new valve guides installed.
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'87 S10-Blazer - SOLD
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