Alright, so no one answered my question on how to view the Sparc code under Self 4.0, so I had to figure out how to do it. :(
Here is what I was able to grok from snooping around:
To find the 'Nobjects' for a certain receiver, selector pair try:
_FindNmethodsRcvr: 9 Selector: 'printString'.
Where 9 is the receiver type where you wish to see the nmethod objects for, and the selector is 'printString'.
Then from the output in the startup window, choose an NMethod object to view the code for, and issue this prim.
Where 16rdeadbeef is the address from the startup window of the actual NMethod object you want the code on.