Definitely douse them with Kroil or PB Blaster a few days before. I have had success by heating the head of the screw dull red, let it cool for about ten seconds then douse it with Kroil or PB Blaster. The heat draws the penetrant in. Then try an impact drill as Kevin suggested.


Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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