fixing stripped plug holes in head.

That is not always correct, JB weld is not recommended for use on engine blocks in relation to high heat areas. One of the reason being is the thermal properties of the JB weld material differs greatly from that of cast Iron thus being it heats up and cools down at a different rate, thus creating cracks and flaking in the JB weld. This can lead to a premature failure if a big chunk of that stuff cracked off and worked its way into the cylinder.

Also JB weld has a maximum operating range of 500 degrees F (http://www.jbweld.net/products/jbweld.php). Knowing this you can associate it with the cold fire combustion of Gasoline (IE the temperature it takes to ignite gasoline from a cold motor state) is 495 degrees F (taken from the physics factbook http://hypertextbook.com/facts/2003/ShaniChristopher.shtml). Of course this does not take into account a constantly running motor where exhaust temperatures can reach upwards of 750 degrees F depending on the ambient temperature and the running conditions of the motor. So if you are stuck in traffic on a hot day yes you can burn the JB weld out of the plugs.

The moral of this story is basically dont use JB weld where it is going to get hot (I have burned out quite a few exhaust studs with JB Weld on them) You might get burned.

 

head has been removed either helicoil will be used or i will attempt to find a head i can reuse.

 

Honestly the best thing to use without getting another head is a Time-Sert. They have a kit made specifically for spark plug applications and retain alot of the properties of the cast iron/aluminum depending on which kit you get.
Here is a link to their website
http://www.timesert.com/html/sparkplug.html

 

EXACTLY WHAT IW AS LOOKIN FOR. had a hard time finding helicoil in the size plug i had to begin with.a day or 2 from now i will have photos of the head gettin done.