a tool to take the exhaust manifold c-spring clamps off can be made from a
regular exhaust system U-clamp.  take the nuts and clamping part off.  now
put the nuts on then flip the clamp part over and put the clamping part
back on.  presto hacko your done.

also as dennis said if you didn't figure out why the gasket blew and check
the head with a machinist straight edge well..... its on you now.

jonathan