Get Line Number from ASM and CAD Part

Dear All,

I have a Design Part  WTPart1 associated to WTPart2 and WTpart3. Also the WTPart is linked to  CAD ASM and CAD Part via EPMMemberLink.  I am able to get the LineNumber available in WTPartUsage link for Design Parts , how do i retrive the Line Number via API for the ASM and CAD Part

WTPart1  (  CAD ASM )

     - -WTPart2  ( CAD Part )

     - - WTPart 3 ( CAD Part )

BR,
Sriram R