Well, I have a "mock" saddle tank a PO put on my truck (A welded rusty steel box
) and I just bought a new in cab tank and am about to go put in, I tried the blazer tank conversion, but didn't have to timeto get the bed off the truck and do the mods to the underneath side of the bed thats needed along with getting the lines bent (Was going in to use 3/8 brake line to as gas line) so I sold it to a fellow member and am just going to go the easy route and put back in the in cab tank until I can get the time to get a cell made and get put in and get rid of the leaky rusty cell I have now. Depends on how much work you want to do and if you're one of the guys that likes to keep things stock.
Just my $0.02.