Bubba won't be much help with a gas MB if the diesel
is beyond him. There are many more things that can
go wrong with gas models, unless you are talking
early seventies. That is one reason I like the diesel,
with the exception of a special compression gauge
things are easier to troubleshoot. There is a huge
list of expensive parts on the gas engine. The motor
itself is not much more but everything around it is.
Don't let the lack of a competent tech change your
mind about buying a MB diesel. If you do, you should
buy something pre 74' so Bubba can work on it.