Since getting the exhaust system back together and the starter fixed, I
am now working on finding out what caused the drop in mileage.  Without
any adjustment changes, the only thing I have done is seal up the
exhaust system and replace the plugs with some platinums.  What I had
installed was some old Splitfire plugs that were due to be changed.
Mileage was a consistant 21.5mpg with the cracked exhaust pipes but
because of the support brackets, the exhaust held itself together pretty
well and thus didn't pass smog but still gave me good mileage.  With
that being the only change, it seems that I am getting about 20mpg now.
Took one reading on the O2 sensor and it was .556 which is high but I
would have thought it would be more in the .5 range (.45 being optimum I
believe).  I haven't made any adjustments yet but plan on checking the
timing, checking for any exhaust leaks developed, intake leaks and
checking the CO or air/fuel ratio (when time permits and I am not
freezing my tail off due to the drops in temperature).

I am looking for any other suggestions on what I might look at or
experience with platinum plugs versis regular plugs.  This van used to
get a consistant 22.5mpg not long ago.  Compression is good and it is
running very smooth right now.

More to come on the flanges after I recheck for any leaks.

William