🚀 go-pugleaf

Greetings!

   I would like to produce a document which is double-sided with
the inner margins set at 1.0in and the outer margins set at 0.5in.
I am using doublecolumns with eplain-1.9. 

I set the \topmargin and \bottommargin at 0.5in each, then initialize
the \hoffset with 

\ifodd\pageno \hoffset=0.0in \else \hoffset=-0.5in\fi
(an article may start on page 26, for example)

Then I need a way to reverse the margin settings at the end of the 
page in preparation for the next page. First I tried to tack the 
\ifodd statement listed above onto the \headline{} routine, since I
thought TeX would look at it during the \output routine
at the end of every page. This failed to get the desired effect. 
Then I tried to make the margin change by sticking the \ifodd statement
in what I thought was the \output routine token list. No dice.
I've spent 3 days squinting at the TeXbook, TeX for the Impatient, 
the eplain docs, the TeX FAQ file, and searching several ftp sites
for a ready-made macro. 

Any advice or pre-fab macros would be greatly appreciated.

Edward Earl van Cura
evc@ccwf.cc.utexas.edu