ipv6 routing header dissector update

I'm sending and processing IPv6 packets with a routing extension header (protocol 43). I'm using a new type field (within the protocol 43 extension header) as the contents are custom. Wireshark understands how to dissect protocol 43 type=0 packets but not my packets. I'd like to either:

• override wireshark's protocol 43 dissector with mine which can parse protocol=43 and the contents of my new type field.
• tell wireshark to invoke my dissector when it sees protocol 43 with my type field value.
  

What are the steps to do either of the above?

Note that currently my dissector is written in LUA.

Thanks