Anyone using Audio Innovations 1000 SE?

Need some help!

I just bought a second hand Audio Innovation 1000 SE. I have a problem with the positioning of the driver tubes. The two monoblocks have different positioning for 12AU7 & 12AX7 tubes.

One mono positioning is:
12AU7 12AU7 12AX7 12AX7

The other mono positioning is:
12AU7 12AX7 12AX7 12AU7

I knew one of the mono have wrong driver tube positioning but I want to know which one is correct. The previous owner already lost the manual and he don't know. My friend said the two driver tubes are not interchangeable and it might damage the amp.

Please help.

Thanks,
ANT