Tim,
The bolt hole circle on a Canadian carrier/ring gear is 3/16" larger than that found on U.S trucks so the options are:
1. Obtain a carrier from the U.S. (Patrick Dykes will suggest this as he has probably never seen a Canadian carrier and would not have had a comparison opportunity.)
2. Machine the correct bolt circle which will elongate the holes 3/32" towards the center. ( A BC bolter took his to a machine shop and paid an outrageous amount to have it done)
3. As the existing spotface diameter is acceptable carefully elongating the holes with a rat tail file would probably work and I was told by Scott's Super Trucks that some customers have done it that way succesfully.
Here's a few pic's:
http://rides.webshots.com/album/573906758RqiOTm
