spark plugs overheating

[david-needs-help]

I have a 1997 dodge ram 2wd that I bought 2nd hand...maybe even 3rd hand....anyway, the spark plugs on the #3 and #6 cylinders keep overheating. I'm on my 4th set of plugs in the 5 months that I've had the thing. The engine was on when I bought it and the diagnostic on it came back that there was "random misfire on #3 and #6 cylinders".
I did the obvious...changed the distributer, points, rotor....changed the plugs and put in Bosch platinums on all 8 cylinders....changed the plug wires....changed the oil and filter, pcv filter....then it seemed that every 4 to 6 weeks, I've had to change those two plugs out due to misfire...the engine light never went off. The plug wire to #3 burnt up 2 time in less than 3 days. What can be the problem...a mechanic friend suggested changing the injectors for those two cylinders...does anyone agree?

[fred]

how about using a colder plug... and try using coppers instaed of platinums..