If you want to go super cheap and not replace anything, then do the $20 ghetto method:
If you want to do it right, then take that money and spend it on some additional upgrades while you're in there. If you have the means, then drop the entire rear subframe. It's really easy and gives you a lot of working room on the table. If not, then watch this video:
This looks like a good video for the diff bushing and subframe collar.
Diff bushings (front and rear) - $64
https://www.z1motorsports.com/z1-produc ... 10356.html
KY Jelly for the poly bushings:
Tool if you don't want to use a sawzall
https://www.z1motorsports.com/transmiss ... oPurchased
Optional, but highly recommended in addition to the bushing:
Bell raceworks diff brace
For stock diff cover:
https://bellraceworks.bigcartel.com/pro ... iff-covers
For Diff with Z1 Diff cover.
https://bellraceworks.bigcartel.com/pro ... ned-covers
If you drop the subframe and want to go further while you're in there, then:
Subframe collars (easy method, doesn't actually require dropping the subframe)
https://www.z1motorsports.com/transmiss ... 12015.html
Poly subframe bushings (requires removal of the subframe)
Ignore the fact it says it's for the 350z, it fits the g37/370z
If you still have money and time, then move onto your axle bushings, transmission mount, and engine mounts..., but that gets expensive and I don't think you want to go there. You should do the additional diff brace to distribute the load on that one stud when you stomp on the gas.