#1
Hi. I know I`m bit nuts, but...

I want 100W 3 channel amp and which would be:

1) Marshall Super Bass
2) Dumble ODS
3) Sunn Model T channel 2

I guess it would be possible to somehow put together 1 and 2, with separate eq and maybe even separate preamps, but what about 3? I`ve seen somewhere that Model T has some differences in the power amp. 

But I mean, it`s all moded bassman!! It gotta work somehow, right?
#2
Take a look at the schematics for all three amps. The power amps are not the same for any two of them. That doesn't mean you can't make some compromises and stuff three preamps into one amp with a close-enough power amp, but "it's gotta work somehow" tells me you might want to do a bit more research!

There are plenty of designs with these multiple preamp models, but this is a lot to try to do for one amp, especially if you're not very familiar with how to go about putting them together.