I'd like to convert my 1973 Vibrolux Reverb to blackface spec. Is anyone familiar with the kit sold for $129 by Dan Torres Engineering? (http://www.torresengineering.com/newvibrevamp.html). It's hard to tell from the description whether this kit converts SF to BF spec. Also, has anyone ever made these mods themselves? How difficult is it? Thnx as always!