how to wire a 12 lead motor for lowest possible current draw
If the motor was changed because the rebuilt blower needs a more powerful motor, there is certainly nothing that can be done.

If the motor is grossly oversized for the load, it will not draw the full rated current, but it will likely not draw as little as 20 amps either.

If the motor is grossly oversized and you change it from delta to wye, it might still be able to operate the load and draw less current, but probably not enough less. It might also be at risk for overheating even though the current is lower because it will be operating at a higher slip leading to increased rotor heating. I am not certain if that is possible, but it needs to be considered.

If the motor is grossly oversized and the supply voltage is the lower of two nameplate voltages for the motor, the motor could be operated with half of the windings disconnected. That would only work if the actual load is less than half of the motor rating.

It seems extremely unlikely that any makeshift solution will work. Someone will probably need to bite the bullet and do what is required for a proper installation.