I drove from the Keys to Jax up I-95 after Thanksgiving and at almost every overpass in the Boynton, Delray, and West Palm area there were trumpers waiving signs and flags. Inexplicably, people don't hate him down there. I expect he'll try to put it near downtown West Palm.
I visited friends in Oakland Park (at the back of that canal system) several times last year (and the prior). Just about everyone with a boat, which is A LOT of people in South FL, is a Trumper.
Palm Beach County has a lot of family friendly towns that are conservative, such as Delray Beach, etc etc. None of this surprises me. Florida is a family-friendly conservative state, for the most part, and at this stage in my life and from my perspective looking back on my life as I know it thus far, count me in as someone ok with that.
I think Trump will do just fine putting his presidential library almost anywhere in this state, and I wouldn't be surprised if he is able to locate it in Palm Beach County. No matter where he tries to put it, there will be a bunch of protesters. The liberal cancel mob will undoubtedly fly people in from other places entirely just to attend protests. At this point, who cares.