What's the best way to remove these studs?

 

 

And just my luck... Put everything back together and started filling the radiator, only to discover that now there is a coolant leak just below the outlet hose at the top. What next?

 

New radiator installed. She runs! Misfire is gone. However, I lost about 3.5 liters of coolant/water mix when I swapped out the radiator. I used the remaining concentrate and filled the rest up with water. So now I'm not sure if I have a true 50/50 mix. I burped the system and drove around the block. The needle on the temperature gauge is pretty much right in the middle, maybe a hair to the left of middle. What is the optimum engine temperature? And given the loss of coolant, would you advise a complete flush and refill as soon as possible?

 

ALSO, QUICK UPDATE:

She idles much better than before, about 700 rpm, and so far no misfire codes have returned. But I can still feel a slight tremor when idling that feels like it wants to get worse but never does, not so far anyway.

 

Alright, I was on the way to the dump when the CEL came on: P0430 - Catalyst System Efficiency Below Threshold.

Right now the only problem I've noticed after replacing the heads has been a slight tremor or engine wobble. When I bought the truck I was getting the misfire codes along with P0430 sporadically. I wonder if these were in fact independent problems, or the latter was due to the misfire and my catalytic converter is bad. I sure hope not. Ron and others, any ideas here?

FYI, I also replaced the driver's side exhaust manifold. I wonder if I need to re-torque the manifold where it connects to the exhaust system?