Be careful with the comparisons relative to fuel load.
Some of these cars could hold a lot of fuel so as to minimize pit stops in long races that weren't that hard on tires (like Daytona and LeMans). If you look on the Ferrarichat vintage forum the pictures showing the teardown of a P4 (0846) show almost the entire sponsons on the car are fuel tanks. Jim G (who also is on this forum) has weighed his P3/4 Ferrari (the real thing) and had reported an empty weight of 1850 pounds. The LeMans data has a P3 (should be very close) at 2176, a weight delta of 326 pounds. In addition most weights I have found for a Mark II are showing between 2306 and 2450, and the LeMans data shows them at 2798, or 350-500 pounds higher than the oft reported dry wieight. Maybe the LeMans data had them with driver and fuel, or maybe full of fuel. This was supposed to be scrutineer's figures so it was likely taken before the race, and the cars could have easily been full of fuel at that point. Fuel weighs about 6 pounds per gallon, so 50 gallons could easily make up the weight difference we are seeing here. If the weight included a driver at 175-200 pounds, then we are talking only 150 pounds of fuel, or 30 gallons, which these cars easily held. Jims P4 had two bladder tanks that looked like they each could have held 20-25 gallons.
Either way, they are not consistent with DRY weights that I have see for the same cars in most other places. I have a spreadsheet that I was compiling and according to that most replicas are a good bit (about 300 pounds or so) heavier than the real race cars. Not that it isn't to be expected, just a fact of life. The only inconsistency I have seen is that a couple of cars that are reported as being as "exact" reproductions of MarkI and II's appear somewhat heavier than the other data I have found on the originals and I have no explaination of that, other than maybe the A/C and vent systems are adding some weight and that maybe they are using a bit thicker materials since these aren't race cars anymore.