I think you'll find theres a wealth of information both within the forum and in the WIKI. To be fair, the mods do a very difficult job in deciding what warrants inclusion in the WIKI and in reality they'd have to be on it full time just to keep up. Its not the easiest format in which to create an easy-to-browse help section but the WIKI is certainly growing all the time - keep an eye on it.
The only sure way to absorb the full ramifications of tackling bodywork is to actually get stuck in yourself. You only have to look at the varying state of decay with some T25s (and many I would not have bothered tackling to be honest) to appreciate how difficult it is to provide a one-size-fits-all guide. I actually left out part of a floor in one job as I felt it offered minimum structural integrity and created a water trap. Others have modified parts of the structure to avoid repeat episodes of rot. Sometimes these jobs become a personal decision and no matter how well written up, others will take a different view. Its also a skilful business and over the years I've encountered some very talented individuals, including Malcolm Rookes (Wivenhoe) who I swear could sew the Titanic together.
There are ofcourse many good books around that concentrate exclusively on restoration including one that covers renovation of the VW beetle which is not out of place here. The fastest way to learn would be to buy a Type 2, leave it on the drive and just wait. Before you know it you'll be welding out6riggers and goodness knows what else.
Your approach is spot on Xpress, but I think you'll struggle to develop something with so many variables and indeed skill levels, as others will no doubt verify. As someone once said when I was overhauling their brakes "How much will it cost?" - "How long is a piece of string" I said. Welding is welding but those with limited skills won't approach the job in the same way as an experienced welder. In the end it comes down to recognised methods used widely throughout the industry which are already covered by so many other sites out there.
In other words, the approach isn't T25 or even VW specific. What 80/90 does very well is show the construction and availiability of panels - thats all a welder needs to get on with the job. Technique really needs a video (80/90 bandwidth couldn't run to that) and there are plenty of those on You Tube. Put that way, I'd say its beyond the scope of this site.