Novoflex EOS Retro reverse adapter
First, the Novoflex unit is very expensive. Second, duct-taping two lenses together will leave you a mess. You can buy reversing rings which screw into the front of two lenses, linking them together. When you do this, the bigger the difference between the two lenses the better - e.g., a 100mm on the body and a reversed 35 mm in front of that.
Any insults, implied anger, bad grammar and bad spelling, are entirely unintentionalal. Sorry.