OH! if you plan to drive it up to canada and keep it there, then yes, you need to follow a certain procedure to import it. The B4 form does not bypass the import process, it just keeps them from taxing you on the car and you will want to present the B4 form to the border upon import so that you can waive taxes. there are a LOT of little steps to get it imported and it can get confusing. you will want to start searching the "settlement" board on here for the breakdown. She will not be able to get it insured or registered in Canada until it's properly imported.
The process goes - initiate the export on the US side, present import info to CBSA 72 hours prior to import, bring car to border to import, pay the RIV fee online to receive the inspection form, have the car inspected by the registered mechanics for importing (usually canadian tire) (cars usually need daytime running lights installed/turned on - dealers usually don't understand what you want and will refer you to canadian tire since they are known as the registered import mechanics), send RIV the inspection form to finalize import, get provincial inspections, insure the car, register the car. Again, there is a ton of legwork, but unless you have major mechanical issues with your car, it's relatively cheap and quick.