Cool that you at least give it a shot. Florida is a beast to bike. I've done various parts of it. I am doing a loop starting and ending in Del Rio in April-May. Taking 90 from Del Rio to Marfa than doubling back through Pecos, Midland, Eldorado. So is 90 still a bitch re chip seal in Texas (asking others who have ridden it). I don't want to ride I-10. cause it's no fun plus debris in the shoulder.
I am 72 1/2 . The main thing for me is worry about breakdowns without a bike shop for hundreds of miles. There are shops in Del Rio and Midland - that's it along my route. I have been trying to find someone I could pre-pay to bail my ass out (fix my bike) in the event of a level 2 problem (Level 1- easily repaired, like a simple flat, brake adjustment). Level 2 - someone with mechanical acumen could repair (broken chain, more substantial gear or brake problem. Level 3- Needs a bike shop. I would also pay actual expenses. Not a sag but an insurance policy. So far no takers. Have tried bike clubs, associations, everything. My wife is worried silly. But bike is in great shape and probably I will be fine. There is always an element of risk.
Back to you - sorry you couldn't complete it. I've gotten clipped by a sideview mirror in the Florida Keys, also practically run off the ride several times. Any possibility of another, less difficult trip?