The first public announcement of Bruce Greenwood's casting for this movie took place in an interview Greenwood gave to The Vancouver Province on September 26, 2004 while attending The Vancouver International Film Festival:

Next week, Greenwood's in Utah for The World's Fastest Indian, directed by Roger Donaldson (Thirteen Days) and starring Anthony Hopkins.
Vancouver Province 9/26/04

The official announcement of Bruce Greenwood's casting appeared a few weeks later in the trades, along with the official casting of Anthony Hopkins:

Hopkins hops to chief role in 'Indian'
Will play motorcycle legend Bill Munro

By CATHY DUNKLEY
Variety 10/18/04

Tokyo-based OLC/Rights Entertainment is financing the pic with the New Zealand Film Production Fund and the New Zealand Film Commission in association with 3 Dogs and a Pony.

The film, budgeted at $25 million, is lensing in and around Salt Lake City and in New Zealand.

Diane Ladd, Paul Rodriguez , Bruce Greenwood and Chris Lawford round out the cast.

Hopkins stars as motorcycle legend Burt Munro, who, after perfecting and modifying his 1920 Indian Scout motorcycle, ventured across the world to fulfill his lifelong ambition to race at the Bonneville Salt Flats in Utah. He ended up setting a new world land speed record.

Pic reunites Hopkins and Donaldson; they worked together on 1984's "The Bounty," in which the thesp starred as Captain William Bligh.

"Indian" is being sold internationally by Satoru Iseki for OLC/Rights Entertainment (Japan, Korea, Taiwan); Donaldson and Hannam for North America; and Kathleen Drumm at New Zealand Film, who is handling all other territories.