Annoying knock from camshaft front pulley area

[Charles P]

If it is the original square headed retaining bolt, then yes.  I think you could raise the block sufficient to remove the retaining bolt without disturbing the pistons in the block.

The other option is to use a Dremel to shave down the square headed bolt and then butcher it out with mole grips or similar.  Take great case with the mess though.

C