[rescue] T1000 CPU Speeds

[Ken Link]

I have a T1000 with a 6-core 1.0GHz CPU. I'm looking to upgrade to the
8-core CPU, which officially only supported 1.0GHz speeds but Sun made a
1.2GHz variant for the T2000 and a 1.4GHz variant for the T6300 blades. All
appear to be the same T1 architecture. Oracle published a document
outlining the differences between the T1000 and T2000 here:

https://www.oracle.com/us/corporate/contracts/sun-server-table-070697.pdf

What I'm wondering is whether dropping in a 1.4GHz or 1.2GHz CPU into this
T1000 will work even though it's officially not supported. Has anyone done
this before? I'm not familiar with CoolThreads servers but I've tried using
unsupported UltraSPARC-II CPU modules in Ultra 2/220R/420R chassis and was
unable to boot, which is why I'm asking before buying anything.

Part numbers for those following along:
1.4GHz: 527-1286
1.2GHz: 527-1200
1.0GHz 8-core: 527-1201
1.0GHz 6-core (current): 527-1202

Thanks!
Ken