The hardware manual for the IBM Thinkpad R31 is at the link below. It contains diagrams for taking apart the laptop.
Right click this link and select Save Target As... to save the manual to your hard drive:ftp://ftp.software.ibm.com/pc/pccbbs/mobiles/02r2913.pdf
You will need Acrobat Reader to view the file. If you don't have Acrobat Reader it can be downloaded from this page:http://www.adobe.com/products/acrobat/readstep2.html