4kq diff seals...

[rjandrew@post.cis.smu.edu (R Justin Andrews)]

hello everyone!
My 4kq has been great lately except for both window reg. cables
breaking w/in 30 mins of each other last night...
I have the parts to fix these ($3.50) cable + hardware....

but the more important issue is my rear diff seal is leaking....
How hard is this to do and will I need special tools?
Please don't tell me I need to yank the diff.....
When my fluid level starts to drop I get an occasional crunch on hard 
accelerating/turning/shifting to 2nd..... Never occurs when fluid is topped
off... I am assuming this would make sense? Also the diff starts to whine 
a LOT when the fluid gets between 1/2 to 1 quart low...

Any suggestions appreciated!
TIA!
Rich Andrews
rjandrew@post.cis.smu.edu