[pdftex] Compressing a font

[Martin Schröder]

Hi,
we have a customer that wants two variants of Helvetica Compressed
that are even more compressed: to 80% and 75% of the normal width.

The ExtendFont special from the mapfiles doesn't really do what we
want (it steals sheeps).

Microtype (e.g. \pdffontexpand\font -499 500 7 autoexpand) seems not
to be designed for this - at least I don't get the results I want.

So how do easily I get a properly compressed font? FontForge?

Thanks in advance
   Martin