Tell me does the battery have new clamps on it? You know the red and gree ones? If so the powder coat on them is the problem. While they look pretty in the package they will cause a host of problems because the coating is on the sides that are going to touch the post and wires.
Also if the ground wire from the block to the engine is missing then the clutch cable can become the ground. This can be a problem as it can burn the cable.

This is the poster child of problems. Powder coating stops electrical current.
So by looking at this picture you can see how little contact is made where it counts.
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