How often did Fender build one off or custom guitars back in the 50s/60s?
Yea, gruhn's in Nashville. Clapton took 6 @$100 each, built blackie, and a few more for himself, gave one the Harrison and one to someone else.Hendrix got a lot of his guitars at Mannys in NY. Clapton bought his 5 strats (or was it 3?) in the late 60s somewhere in the US (can't remember if it was famous place or not).
And from those he took the best parts of each and built his black strat he used throughout the 70s and early 80s....
so no. Clapton didn't get his signature guitar until late 80s....