I've had a saved search on eBay for what seems like ages waiting for this particular edition of Popular Motoring to appear. When I acquired my Shorrock back in the early 1990s it came with a copy of an article ripped from this magazine regarding the fitment of the Shorrock to the Herald. It's great to get a copy of the entire magazine - for the bargain price of £1.25!
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160380347798
You can read the article here...
http://9700vc.blogspot.com/2007/10/supercharge-your-car.html