I stood about 30' from ColinDibley in 1977 when he hit 149mph at the GoldenGatewayTennisClub in SF. Colin is an ape armed monkey, maybe 6'3", but only when he was slouched over, normal for him. His wingspan was probably just under 7'6".....almost like MichaelJordan's.
PrimoCarnera glassed his DunlopMaxply with extra glass at the throat thru to include the whole head, but only laminates, not a wrap. I watched that too, from FTC's stringing booth.
Colin was maybe in the top 30 men's pro at the time. VictorAmaya, a lefty monster at 6'6", served serveral serves at 144, but broke TWO rackets in less than 20 serves.
Milos, if he could get a racket that lasted, would serve harder, but not much more than a couple mph's.
Sweetspot on wood rackets were much higher, farther from the player's hand, and players could change string tension to match their preferences with the old softer wood rackets.