Only worthwhile if the original phrasing is used. The sanitized “Let’s Go Brandon” is too timid.
Maybe “FUL” (”F*** You Lightfoot”)?
T-Shirts already available. F.U.L.L. In the colors of the flag of Chicago.See below.
https://www.shopjackass.com/product/f-u-lori-lightfoot-tshirt/16?cs=true&cst=custom