[SunRescue] Earliest sun3 sunos files?

[BSD Bob the old greybead BSD freak]

Offhand, what are the earliest available sunos files for sun3 architecture?
I noticed Bill had 4.0 in the archives and a 3.5 exists in the sun3arc
archives.  I have loaded up the 3.5 and it seemed to work, fine.
But, I was curious if anything earlier was about?

Also, any chance a sunos-2.0 for a sun2 might run on a 3/160?

Or, can a 2/160 cpu be subbed into a 3/160 to make a 2 level machine?

If so, anyone got a spare sun2 cpu card they might part with?

Thanks... just thinking about some play shennanigans.....(:+}}...

Bob