Best you do it properly. Contact these guys and buy the pivot kit and the new teflon bearing kit. I did and have been very happy with the result on my 8".
http://www.astrosystems.biz/pivot.htm
Read up here on updating a 12":-
http://www.iceinspace.com.au/index.p...41,451,0,0,1,0
Note that Scott also moved the Az teflon bearings in closer to the centre. (I've since bought that 12" from Scott.)
Good luck!
