RPM, aka Bearing Bob wrote:

TKOPerformance wrote:

I would pull the block drains when flushing.  I usually put petcocks in engines I build for this purpose in the future.

 
Where can a guy find a quality petcock these days? I get one use out of them before the T handle spins on the shaft on the ones I've bought lately.

 
A rad shop might have them if you can find one of those!