Tom, and all...
There are a few other ways to come up with complete full-size plans.
-- If the linework in the original magazine construction article is reasonably fine:
-- -- Determine the scale of that page plan and hit a well-eqipped copy shop for a copy enlarged to full size. Generally, this is not a copyright violation, particularly if you contact the original printer and learn there are no more plans in stock. It is like making a working/backup copy of software so that you don't damage or corrupt the original media it came on. Just don't go trying to sell numerous copies at a profit!
-- -- TilePrint is an application that scales up a scanned image in computer memory and divides it into laser or ink-jet printer page 'tiles' - hence the name. A bit more tedious to piece them together, but nicely accurate in dimensions and edge-matching. Check Dave Fritzke's site for more about TilePrint.
For a working copy of the paste-up, check a local UPS Store for an inexpensive 100% copy to work with. The paste up is awkward.
Again, check first to see if someone holds a current copyright, and get it there if you find one.
You'll still do well with a 100% size working copy to spare the original.
Newly drawn CAD plans are great and prettier than many originals, but if anyone gets silly about authenticity, recreating the originally available plans should be convincing.