Working on press fit freeze plugs with the engine in the vehicle is a PITA. I'd suggest using the rubber expansion plugs, after a good cleanup with a wire brush in a drill motor. Pull the manifold assembly and those oil lines to get better access to the side of the engine to remove the old plugs and clean the block.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!