That would be awesome if it worked. And turn the basin into a mashtun too.
One of the biggest issues would be the dinky motor, though you could restrict the grains going into the rollers to compensage. You have ~12" of usable roller and that would be a waste not to be a able to use it all, and replacing them with machined rollers isn't going to be cheap. The gap can be "set" with the lever at the top, but i do recall the gap being fungible and slowly opening over time- to have it set and stay set would be problematic as well. The gearing behind the rollers may be up for the task, it's old school americana manufacture and was made to handle squeezing lots of clothes (and fingers).
I have friends who collect these things, these maytags are worth $ to the right person/sucker.