Your choices are to purchase MacLink Plus from DataViz Corporation (see below) or to save from WordPerfect 5.1 as a 5.0 or 4.2 file which Claris products will be able to open.
Write/Draw/Works can only save as a WordPerfect 4.2 file. However, WordPerfect 4.2 files can be opened by WordPerfect 5.0 and 5.1.
Tip: when opening WordPerfect 4.2 PC files in Write/Draw/Works, in the Open dialog box, select WordPerfect in the file type popup menu first, then click on Open (do not leave the popup on 'All Available').
WordPerfect Mac
ClarisWorks 2.0 and MacWrite Pro come with a WordPerfect 2.x Mac translator which can both open and save. MacWrite II and ClarisWorks 1.0 owners must upgrade to obtain this translator.
DataViz Translators
MacLink Plus by DataViz (800-733-0030) includes a WordPerfect 5.1 translator which supports reading and writing WordPerfect 5.1 PC files. MacLink Plus adds additional XTND translators as well, including one for WordPerfect 2.x Mac.
NOTE: The XTND technology is built into the MacWrite II 1.1 application, therefore a Claris XTND System does not ship with MacWrite II.