DiMarzio Ultra-Jazz 5 radius question

[Monkey]

I am building a five-string fretless, and decided to try a flat fingerboard. I bought the Ultra-Jazz pickups, and it turns out that the pole pieces are radiused. The outside pole pieces are flush with the case, and the middle pieces are the highest. I'm worried about unequal string-to-string output.

I am in the last stages of finishing the bass, and the neck is done, so I'm stuck with the flat fingerboard.

Would it damage the pickup to ground down the inner magnets?

Is there a way to do this without boogering up the plastic case?

Any advice would be appreciated.

[Luke73]

Put 'em in and see how it sounds.

If you don't like it, get different pickups (or a radius block and radius the fingerboard).