I recall no font requirements in the original instructions and the OMB form requires customization to insert the bank info. That said, I would follow the "clear and conspicuous" disclosure requirements we are used to. So avoid a 6 point font but increasing the size or decreasing it slightly either way shouldn't be an issue, IMHO.
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AndyZ CRCM
My opinions are not necessarily my employers.
R+R-R=R+R
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell