payload compartment

Building a regular 2.6" cardboard Madcow DX3. Was following along the instructions, but there's nothing there about how you attach the nose cone. The DX3 has a payload section, the shock cord attaches to the bulkhead at the base of it. Nose cone in the top. But what do you do with the nosecone...

I know were not supposed to use "any significant metal parts" but i have been experimenting with electroplating nickle to ABS plastic. i was wondering if I were to plate nickle to the payload section for increased durability if this would violate the safety rules? the plated section would house...