An example that I have that is working with option A. Even though the raw data is clearly base64 encoded it is being parsed as a human readable string 
     $tmp_part->bodyhandle->as_string

[download]
There is no "Content-Encoding" header in the raw mail.

Here's the relevant part of the header: 
X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:cont
+ent-classes:message MIME-Version: 1.0
Content-Type: multipart/related;

        type="multipart/alternative";
        boundary="----_=NextPart001_01CDF2E2.B6A090C6"


This is a multi-part message in MIME format.

------_=NextPart001_01CDF2E2.B6A090C6 Content-Type: multipart/alternat
+ive;

boundary="----_=NextPart002_01CDF2E2.B6A090C6"

------_=NextPart002_01CDF2E2.B6A090C6 Content-Type: text/plain;

charset="utf-8"
Content-Transfer-Encoding: base64

SGkgU3VlICwKCldpbGwgYmUgaW4gdG91Y2ggaSBhbSB0aGlua2luZyBvZiBkb2luZyBhIH
+RyaXAg dG8gSXRhbH

...

[download]

In reply to Re^2: MIME::Parser parse_data by boosth
in thread MIME::Parser parse_data by boosth

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