I'm about to pull the heads from my 2000 T/A and replace them with 243's. Is it not possible to drain the block prior to pulling the heads, so antifreeze doesn't get everywhere and get in all of the head bolt holes? On the old GM V8's, weren't there plugs you could remove to help do that?

 

I have found that by pulling the water pump you can get much of the coolant out of the way before the head swap. I have read, but not personally tried, about using a wet/dry vac to pull the remaining water out of the block.

 

I have done it by removing the water pump and then taking a air gun to each coolant crossover hole on each head and sprayed air into the head and it will force some of the excess colant out of the heads and block. Obviously the intake and coolant crossover pipes have to be removed to do this.

 

my LM7 block has a allen-head coolant drain under cylinder #8.

 

There is a drain plug on each block side. You need a humongus Allen wrench(at least 3/4" or bigger) to remove the plugs.