There isn't really a "Right" way to do it...its a customization...for the pinion flange, the reason you'd have to cut the centering pin is because the driveshaft its mating to was designed not to be used with one and wont accept it, so it will work the way its supposed to work... with that particular driveshaft...for the side flanges the thread/vs non thread thing is easily corrected with a few bolts...I bought some from the dealer anticipating the reverse thread issue but ended up reusing my bolts cause my doner's matched and they have been fine for years....


Anyways car-part.com and hollenger are much better for these parts...you just have to know the doner cars better then the junkyards cause they suck at labeling...I got one with the 28k miles and one with 11k miles each was under 400 (Canadian (say 300 USD ish)..this was couple of years ago.

I still say OP should get under his car and determine what he has flange wise, it would narrow down the variables substantially....

 

There's not really a variable except if he has a manual it's a 4 bolt and auto is 3. Simple

 

Thats not true. There's also a 6 bolt flange and depending on the year (07-08 G35, 08 G37, 15, 16 Nismo, 09+ Manual sedan or coupe) the three bolt and 4 bolts were used differently (not just delineated by auto and manual)...also the side flanges(stub axles) and may have threading etc...anyways I already mentioned a bunch of these differences in post #7 and its in the linked threads in that post too.

 

I found a 3.69 VLSD diff from a 2008 g37 with only around 60k on it for $189

My 15 Q40 is 7AT with the 3 bolt flange so it should work right? From my understanding it should just bolt right in without having to buy any bolts or swap axles?

 

So I got my rear differential delivered today and the packing was beat to hell and it appears to have been dropped because one of the stub axle was bent. The good news is fedex is going to pay for it so I ended up paying zero for a 3.69 VLSD with 62k!! Now my question is will the stub axle from my Q40 fit this or do I need to get one from an 08 g37?

 

Well thats a good deal.

depends on which one is bent... on the LSD one of the stubs is shorter than the stubs on the open diffs...if its the shorter one you're out of luck, if its the longer one you should be able to use the one from the Q40..just gotta pop them out and have a look, use a pry bar (it'll seem like they are bolted in at first, but they will pop right out)...once you have it out you may be able to bend/pound that flange back flat though...

You're gonna want to check to see if the stubs match your axles' threading anyways at this point too if you haven't already.

BTW you might as well change the side seals at that point they are super cheap. Good luck.