Portable Plus - Additional RAM

[Michael Fehlhammer]

A question for the Portable Plus experts: ( Hi Dave? )

I would like to have more RAM than 1.5 Mbyte in my machine ( 512kB internally and 1 MB RAM drawer ).
How could I achieve that? Can the RAM drawer be upgraded to 2 MB?
If there is a way, can anybody provide a link to a documentation of the procedure?
( Certainly I lack the skills to accomplish that by myself, but I hope to find someone who could do that ).
Thanks in advance!