In command line, you'd have to use something like:
Code:
mobi2mobi --outfile output-file --exthtype 113 --exthdata some-ASIN-number input-file
mobi2mobi --outfile output-file --addexthtype 501 --exthdata "EBOK" input-file
where the second input-file should be the first output-file. I don't know if that's possible (or how) with the GUI. And I don't know what are the restrictions for a valid ASIN number.