Y30 cedric diff problems

[matt finney]

hi.im a new member on here and was hopeing that someone out there might be able to help.i own a 1986 y30 cedric which has a very noisey diff! the problem will keep getting worse as it has a rb25 skyline engine in it at nearly 350bhp.now on coilovers all round and s14 front hubs and skyline steering rack and subframe,oh and the diff is welded.
what i want to know is.is there a diff from a other nissan that would fit in my axle and take the extra power?? id love to have a lsd in it instead of welded diff but i dont know if any was made for a y30.
if anyone can tell me anything about this id be very greatfull.cheers