Diff building for dummies?

Given the wealth of knowledge and experience here, im hoping some of you might be able to give me a bit of advice on freshening up my differential.

Many moons ago, when I was doing my apprenticeship I did a diff build. Fast forward over a decade and I've barley touched a different since.

I'll be working on a Mazda b series 8inch diff (pretty much the same centre as the rx7) over the Christmas break and am feeling a little out of my element. While I'm sure I'll have no dramas following the workshop manuals procedure I just wanted to get a prospective on how other people go about things. Should I go to town on it and replace everything? Or just do some new seals and check tolerances?

Otherwise should I just take the opportunity to see if I can source An rx7 LSD from a jap importer and do a crown and pinion swap and call it macaroni?

Thoughts and advice will be greatly appreciated.

If it makes no noise and doesnt leak, then I would just change fluid and call it good.

If you're looking to defeat here is a how to I did years ago for a Jeep D44.

All diffs are similar.. Just a matter of crush sleeve vs shims, where shims go for pinion depth, and shims vs threaded adjusters for carrier bearings(and if shims, whether they go under the races or the bearings).

In a nut shell:

-You figure out carrier shims needed to eliminate play(minus preload which I add at the end)

-You choose a depth to set the pinion for initial start. Normally whatever was stock or of the book gives a starting point use that. Sometimes marked on pinion head itself.

-adjust backlash to spec

-check pattern. Move pinion deeper or shallower based on the pattern

-repeat backlash to spec

-repeat gear pattern

Repeat all the above until good.

http://www.jeepforum.com/forum/f19/regearing-marinejrms-xj-d44-992471/

Edit: also here's another link to another diff I regeared, this one without my fancy bearing puller I love so very much: http://www.jeepforum.com/forum/f9/regearing-jake92321s-tj-d44-970997/

Edit again: also here's probably the best tech article you'll ever see on regearing axles: http://www.pirate4x4.com/articles/tech/billavista/Gear_Setup

Careful with Mazda 8", the pinions are all housing specific.

In reply to flatlander937:

Thanks mate, there's some great info there, I'll have a better read through it tonight.

Unfortunately, I'm past the point of just an oil change. The current diff whines something fierce and has a bad pinion seal (which will be part of why it whines, undoubtedly its been low on oil at various points). The spare diff I have appears to have bad axle seals (telltale oil weep at the axle flange)

In reply to Knurled:

Thanks

You mean the cast section that the chunk is mounted in as opposed to the axle housing correct? I know the rx7 has a much longer pinion snout than the b series . Or is there other differences im not aware of?