Generally you have to go either through a Broker or Freight-forwarder in order to clear customs. Unless you have a local CBSA office and you can pick up the B3 form (or on line) and fill it out yourself, you have to look up the commodity number that applies.
Large machinery usually ends up in a freight Co. bonded warehouse or the CBSA warehouse to await clearance.
I have always cleared my own.
https://www.cbsa-asfc.gc.ca/publicat.../b3-3-eng.html
If the port of entry is Vancouver for e.g. you may have to contact a bonded carrier to pick it up and deliver to its local bonded warehouse.
Al.