Dave
I restored an early M49 a couple of years ago with the help of a couple of other people doing the same at the time. One of these guys (Davd Friesen from the US) has a web page devoted to that model Sherpa T, including on his resto of a M49. The other guy (Patrick Frei from Switzerland) produced a web page showing his restoration of the M49 his Dad rode at a high level in the late 1960s.
Bultaco changed the M49 a fair bit from the first series in 1968 to the third series in late 1971. They even sold a kit to convert late model M49s into the next Sherpa T in the series, the M80. I'm sure you will work out where your M49 fits in soon enough.
They are a very historically relevant model Sherpa T because it was the first trials bike in the world that sold in very high volumes. It is the third model Sherpa T and some people consider it the best-looking Sherpa T.
Most of my trials bikes are from the 1970s because that is my era, and I was always intrigued as to why the OSSA MAR was so much in demand when it first came out in 1972, if the Bultaco M49 was as good as they were made out to be. That led me to restore one of each to be able to compare them back to back, and it has been quite a learning experience along the way.
Anyway, I will help you as much as I can with you M49, and here is the web address of one of the bikes I wrote of earlier.
http://web.mac.com/davefriesen/Site/Bultaco_Blog/Bultaco_Blog.htmlI'm still looking for the other web address
David