Uh oh, power steering bolt broke into number one cylinder?

Second one up from the bottom on the left/drivers side of the timing cover. If you take the power steering bracket off of a 340 and install the same bolt without the bracket you usually break the block . 318 and 360's are a very little more forgiving but not much.

You should determine the length you need with a wire or depth gauge if you are unsure .

In the engineering world any bolt only has the extend into the threaded hole the width of the bolt. Its a 3/8 bolt so 3/8 past / longer then the timing cover and gasket would be the correct length. If you are using a power steering bracket add that to the cover and the gasket plus 3/8. Its not a rocket science equation. You can go a tad longer then 3/8 into the threads but I wouldn't go crazy. Check the depth.

Oh yeah don't forget the washer on the bolt.