PART II:
Some argue that Laver was too short to effectively handle the higher bounces of today’s game. I don't agree at all. First, Laver was about 1/2 inch shorter than David Ferrer who has no difficulty handling the bounces of today’s game. Second, fortunately there is some video evidence of Laver’s ability to handle high bouncing balls against Borg, who, to my recollection, according to Vic Braden, had an average net clearance of 10-12 feet. That’s about twice the net clearance of Nadal.
Here are some videos from the same match between 38 year old, semi-retired, Laver, against 20 year old, #1 ranked, Borg, on clay. There are numerous amazing shots by both players in these videos. In the first video, at about 42 seconds Laver punishes a head high forehand with a Continental grip. Also, check out the drop volley at about 1:15 and the inside out forehand drop shot from the baseline at about 1:25. With all of Laver’s power, he was also one of the greatest touch players of all time. At about 1:35, Laver hits a blistering topspin backhand cross court passing shot. At about 1:45, you can see a bit of Laver’s speed and athleticism, at 38.
Here is another video from the same match with slightly different highlights. Check out the backhand passing shot at about 3:55:
Here, at about 1:15, you get an excellent view of slightly younger Laver’s (35?), modern forehand during a win against Borg:
Here you can see another example of older Laver’s topspin backhand against Connors at about 4:30:
Having said all that, and having expressed my view that Laver’s game was modernized from the beginning, and making an assumption that he would compete against Nadal, on clay, with the modern racquet and string of his choice, in my view, Nadal would have a winning record against Laver on red and green clay, but, I also think that the odds are good that Laver would get some wins against Nadal on clay if they played enough matches.
I also think that Laver would be a tougher matchup against Nadal on clay than Federer. First, Nadal has a natural advantage against Federer, especially on clay. Nadal has had tremendous success against Federer, especially on clay, playing his strength (his forehand which, in my view is the second greatest shot in the history of tennis behind Federer’s forehand, but, even greater on clay), against Federer’s weakness, his backhand, especially when Federer is taking balls above shoulder height on the backhand side. As I have pointed out many times, unlike the great backhand slices of Laver, Rosewall, Newcombe, Emerson,
et al., until very recently, Federer did not hit a drive slice on his backhand side, he hit a heavy chop, and was only able to respond to Nadal’s high bouncing forehands with weak floaters that Nadal punished. Second, Laver is also a lefty. Nadal’s cross court forehands would be against Laver’s modern forehands, still an advantage for Nadal, but, not nearly as much of an advantage as hitting against Federer’s chop floaters. Further, Laver didn’t have a weak side, although, as great as Laver’s forehand was, many think that his backhand was even greater, and he could absolutely bludgeon high bouncing balls with his backhand drive slice. Laver would have a court positioning advantage against Nadal because he didn’t run around his backhand and he was just as fast and explosive as Nadal, maybe moreso. Moreover, if Nadal tried to play Laver’s backhand as a primary target, he would be hitting down line, a tactical error, leaving the court open for Laver to hit cross court. I would also submit that there has been no player in the history of tennis who could hit the kind of devastating winners, on the dead run, on both sides, the way Laver could. In addition, in my view, Laver is Nadal's equal when it comes to mental toughness, if not steadiness. Laver will not give up. Federer, I'm not so sure about. I've seen him look like a beaten player more than once.
In my view, Laver’s weakness in this match-up would be his natural super aggressiveness and desire to end points quickly with winners. That would work against Laver in a match-up against a supreme defender like Nadal, even moreso on clay. However, Laver did learn to be patient and rally from the backcourt against the human robot, Borg, and was able to beat him on clay despite being 18 years older than Borg. On the other hand, Laver was the greatest finisher from every position on the court in the history of tennis, and would be far and away the greatest net player in the game today, ready and able to exploit every opportunity he gets against Nadal.
I’m sure there is more to discuss about this fascinating match-up. But, I think I have made a case that Laver would be very competitive against Nadal on clay, assuming modern equipment, and would probably get some wins on clay if they played a sufficient number of matches.
In his peak season on a very fast hard court he lost to teenage Nadal despite having this "more confidence" But yes the obvious take away from that is that Fed wasn't focused in a championship match and rather that contrary to all evidence it would mean Federer would win vs peak Nadal on hards when teenage Nadal could beat him. 
On a quick court Federer if peaking should be able to win the first set.
