As long as you use a lot of soapy water it should be easy. Took me about 20 minutes to put on. Oh yeah, follow the instructions about using tape to remove the lettering from its backing.
I’m sure you will find the color you are looking for. They have over 30 colors.
https://tvdvinyldecals.com/products/premium-cast-vinyl-decals-for-2021-f-150-tailgate
First thing I plan to modify is that old looking radio antenna. Does anyone know if current aftermarket stubby antennas will work? Is it the same size thread on 2021 models as the 2015-2020 models?