Using NIK Collection 3 for legacy photos

I upgraded to NIK Collection 4 which erased the NIK Collection 3 including the older versions of Viveza 2 and Silver Efex Pro 2. Now when I try to edit photos that were edited using the older plug-ins as smart filters it is not possible. How do I restore the older versions of the NIK 3 Collection without overwriting the new NIk 4 Collection?

Ray - The discovery here, by @Wolfgang, may be a solution for you.

John M