Joie good point...the two farms I have dealt with have the tattoo done on site as they are training farms but if the horse in question here DOES have a tattoo it would definitely identify him as TBred :)
I'm also seeing TB. So glad to hear he's been rescued. I live in Ocala, FL where a huge majority of TBs are bred (potentially) for the track. It is sad that there are so many OTTBs that need homes. That is one of my beefs with the racing industry. I do love driving through horse farms everywehere I go - especially when it is foaling time and there are tons of mares and foals in the fields. Let us know if you decide to get him.
He could be anything, but Tb most likely. Too many faults to have been kept a stallion for this long. If you get him, make sure you don't pay much for him. Most in this condition and a stallion, with maybe no training, would be given away or sent to the killer auction.
I don't know your background or experience, but if you are not very experienced around older stallions and the training he will need after gelding, then pass on this boy.