can verify that an SE/30 board plugged into a Classic II chassis makes weird noises and doesn't boot at all...
That doesn't sound good!
I had the same idea some time ago and found this during my research:
it's for a Classic not Classic 2. The Classic 2 is 10 pin as well so it must be different, but just for reference:
Mac Classic
What are the pinouts for the internal power connector at location J12 on the
Macintosh Classic logic board?
Following are the pinouts:
Pin Description
--- -----------
1 +12 volts
2 + 5 volts
3 + 5 volts
4 /VSYNC
5 /HSYNC
6 VIDOUT
7 Sound
8 -12 volts
9 PWM (Brightness control signal)
10 Ground
11 Ground
12 Ground
13 Ground
14 Ground
_____________________________________________________________________________________
Mac SE:
This article is a chart of the pin assignments for the Macintosh SE power
supply connector.
Pin number Signal Color of Wire
1 Ground Black
2 Ground Black
3 Ground Black
4 +5 V Orange
5 +12 V disk Yellow
6 -12 V Green
7 Ground Black
8 Ground Black
9 +5 V Orange
10 +12 V sweep Red