Toyota Repair: Toyota 4x4 SR5 Head Gasket Repair, head gasket repair, blown head gaskets

Question
Hi Ted,

This will probably be a very easy question for you.

I've got a 1993 Toyota 4x4 SR5 V6 5spd with ~200,000km.  I suspect that the head gasket is gone based on a number of observations: steam at the exhaust pipe on a cold engine; coolant always low requiring top up after ~ 3 hrs of running time; no visible coolant puddles under the truck when truck is shut off; and engine idles really rough.  I know these vintage V6's are notorious for blown head gaskets and I've actually had the head gasket replaced by Toyota under warranty @ 100,000km.  So whatever the reason (maybe a bad replacement part?), I've blown the head gasket again.
My questions:
1.  Is there any diagnostics/trouble shooting that I can do to confirm the head gasket failure without taking it into the shop (min charge of $200).
2.  If it is a blown gasket, can the repair be conducted by your average home auto mechanic, i.e. will it require a lot of "special" toyota tools that would render the repair impossible for me?
3.  If the repair can be done by an average home auto mechanic, what would you estimate the time it would take to make the repairs? (assuming I don't have to take the heads in for valve grind, etc).

Answer
I don't know why it would cost $200 to find out if there is a headgasket failure, it can be checked using a chemical block test which only takes about a half hour to complete, contact the toyota dealer to see if they can do this test for you it should only cost around $80.