No need to dig, Steve and this will free you to do something else on the 4th.
It took less than 5 minutes to find a Steve Nelson article on making a bench rest using the ACGG digital "Gunmaker" archive. I'm not sure this is the one you were thinking about but try:
July/August 1991 page 9. If this is not the one it still is a great solution to the problem of steadying long objects held in a vise.
For those of you that don't know, ACGG scanned all of its Gunmaker editions and sells the archive on a DVD. Each magazine is in a .pdf format, has full OCR text and the entire set is easily searchable using Adobe Acrobat Reader.
This is an invaluable resource for gunmakers looking for advice, tips, how-to's, etc. and is an incredible compilation of information from many gifted gunmakers for over 35 years.