I'm getting ready to replace the control arms on my 2010 Corolla.  There is a large bolt with a 19mm head and 1/2" diameter shank that needs to be removed. I know this is a robust bolt, but it has not been touched since it was installed by the factory 14 years ago.  I live in the rust belt so it is heavily corroded.  The 4" long bolt threads into a captive nut so I don't want to snap its head off.  I plan on spraying it down and using my induction heater, but when it comes to removing the bolt is it better to use a ratchet and socket or an impact gun set to a slow speed?  I feel like low and controlled air impact blows would be better than the twisting motion of hand tools, but I know impact guns can effortlessly break bolts so maybe hand tools are safer?  I'm curious to know how professional mechanics remove rusty bolts without breaking them.  Thank you!