A LSD diff that bolts into the housing for your wagon is not that hard to find, the down side is plan on paying $1200-$1500 for one. I found a deal on one for the 1200 coupe I race and it was still $1200. You can try roadster sites like 311s.org etc. there's lots of info on the net about swapping side gear on the truck diff.
I'd strongly encourage you to do you're research. The prices for the 23 spline diffs are getting steep and replacement parts getting scarce. If you have acces to a diff shop that does work for reasonable prices (read takes pity on poor Datsun guys) than having the truck axles redrilled for the bolt pattern you need may be an option.
The days of $600 units are gone..........sigh.
I've been hunting for a way to avoid needing to find a competition roadster diff. I think the truck axles sound interesting, just concerned about what gears I could find and what the actual LSD's break away point it like. I autocross, so I'd like it to actually be kind of low, probably lower than what the trucks were built with.
I'm looking -- at the same time as searching for a Nissan unit -- at other options like RX7 axles (first gen GSL-E) and Corolla GTS units (AE86). Both of those have more "reliable" availability since you can search for specific years and trims to get the axles. Downside is they're both small, I believe the Mazda is a 7" housing and the Toyota is a 6.75" or something like that.
While I only make about 140hp right now, I'm probably going to three link this axle once I find it and so I would like the unit to be strong enough to take around 250-300hp, if I ever feel like getting there. However, anything American or the H-233 (I suspect) will be HEAVY, which I would really like to avoid -- add lightness and all that.
And it's a Nissan! But it's not a Skyline -- so anyone confused by the title should just bail now.
It's a 1992 Sentra SE-R that I bought from Kevin (I don't remember you Ratsun screen name so I'll need to do some research).
First order of business is to do some cleanup on the clear coat. Going at it with polish, rubbing compounds, and wax to try and make it passable until I pull panels to put some new clear on them.
I already tried putting the S13 steering wheel on the car, but there's some interfering with the pins that create connections for the cruise control. This results in a super annoying clicking when you turn the wheel. I'll be putting some more thought into it then re-attacking.
Some MOAR LOWAR and some new wheels and tires coming soon as well.
And speakers. It needs speakers. The stock ones are really... not good.
I flipped the overload leaf in my wagon and it about 2 inches or more. Also ran 15x7 et5 with 195/50/15 tires with no rub at all even with a lot of weight in it. Only rub was driveshaft hit on very hard launches.
I found that I was getting driveshaft/pumpkin slapping once I went to 2.5" inches of drop with a similar wheel tire combo. This was with only an L16, however. It is entirely possible that when you have an L20 or something with more torque than a 1.6 you start to see axle wrap with even less effort.
Love those Mark II's. I have a pair coming from Japan right now. Did you restore those?
They were fairly clean when I got them. Centers didn't need any work, but I put the lips through a wet sanding and a few rounds of hand polishing. The hardware on the fronts is also not great, so I'm in the midst of ordering several new bolts and nuts and soforth.