From January 1992. Scroll down to see the cover and Parts 1 and 2, or click on these links:
COVER: http://ottawaephemera.wordpress.com/2009/08/23/archie-and-the-whole-riverdale-crowd-come-to-ottawa/
PART 1: http://ottawaephemera.wordpress.com/2009/08/24/archie-jughead-and-dilton-come-to-ottawa-part-1/
PART 2: http://ottawaephemera.wordpress.com/2009/08/25/archie-jughead-and-dilton-come-to-ottawa-part-2/
Click on images to enlarge.
I don’t see how that’s possible… the Centre Block of Parliament is the only one accessible to the public without a guide, and the drawings clearly show they’re in the Centre Block.