Does the checklist tell you, you can lean the mixture for take off? Does the POH tell you to lean the mixture for take off? By how much and for how long? Doesn't fuel have a cooling effect?
I'm not familiar specifically with the PA28 180, but I have seen POH entries in similar light singles and twins that recommended or dictated leaning to max RPM (fixed prop) or to an EGT parameter (CS prop) on takeoff at high altitude (>5000' or so). The engine only makes around 75% of rated power at 5000-5500', so the cooling effect of the fuel is less critical than a proper (or closer to proper) mixture.
Back in the 70s when I was flying 172s, 177RGs, and 310s in Puerto Rico on 115/145 AvGas, we leaned for takeoff even at sea level (normally hot & humid -- high density altitude). Without leaning, plug fouling was atrocious! Only the 177RG had any problems with high CHT on climb...