If you own a furling jib instead of a hoisting jib install your forestay as follows:
1. Make sure the stainless steel jib halyard feeds through the top block.
2. Attach the 4mm line to one side of the stainless steel halyard.
3. Connect the shackle to the other end of the stainless steel halyard.
4. Knot the 3mm line to the loose end of the 4mm line. This is your hoisting mouse line.
5. You can temporarily tie away the loose end of the 3mm line to the shackle.