Rear diff breather (this has to be pressed in): 38356-JL00A $5+
Nismo rear diff AL finned rear cover 38351-350DK $125+
Silicone vac hose 6mm for the diff breather ~ 1.5ft $7+
An additional LEFT flange for the OSG LSD: 38220-JK01B $140
SPL rear differential bushings $165+
So it seems like aside from the install and the LSD itself these are the other parts that are essential (other than the fins but they help with cooling so...) for the installation. Add on the misc washers that you said mentioned are variable.
I'll make to let me shop know about these parts. Thank you guys so much for your help. Keep the posts coming if anyone sees anything that may be missing!!