340CSE: memory expansion

[Frank Sheeran <Frank.Sheeran@ska.com>]

A coworker picked up one of these super cheap (at least for Swiss prices).
It has 4MB.  He has heard that it has one expansion slot that can hold another
4MB or 8MB.  He also has an advertized price for 16MB for a "340".

For him, 4MB is good enough for DOS and 3.1.
He doesn't think 12MB would be enough for Win NT for him, so he does not want
the 8MB upgrade.
If he could get 16MB or 20MB total, he would be confident running Win NT on it.

Questions:
   1) Can the 16MB be used in the 340CSE?
   2) Is this a "do-it-yourself" project?
   3) Is anyone happily running Win NT in 12MB on a 486 33/66?

Thanks!

Frank