Hello, Phil,
Welcome to Stovebolt.com.
There are many Canadian members here. They will know the differences/nuances of Canadian GMC & Chevrolet Trucks.
If you engine has ID markings in the same locations as USA Chevrolet trucks,
find and post the codes in these locations.Your Engine Serial Number is: 287861 3946
Someone will decode this and post the information.
I'll crop and rotate your ID photos, and then attach/add them to this post.