This scenario is not really difficult actually. There's enough space, and getting 1,000 guests in 4 years should be no problem, especially for players who successfully completed the previous scenario or even Evergreen Gardens which has the same objective and starts from scratch besides the path system.
Deleting the scenery around the map brings extra money, but decreases the Excitement Rating of upcoming rides and also makes the park less beautiful, therefore, is a bad idea. There's a path which goes underground from the top of the dunes to the sphinxes area. This path is completely unnecessary and (in RCT1) must be deleted, as it adds nothing to the park infrastructure-wise and it has no functional purpose, if not getting the guests lost, so it's wise to get rid of it right away. It can only be redeemed in OpenRCT2 due to improved pathfinding.
As usual, a good start off would include some flat rides and a small roller coaster (like the Steel Mini Roller Coaster or a Shuttle Loop) concentrated on the first half of the land (until the dunes) and, then and only then, keep expanding until the park's full. Extra land is available for purchase and cheap, allowing the park to get way larger, but it's not mandatory as focusing on nicely developing the original land throughout the 4 years, as well as a good use of the underground area, will work just fine.
Here, research at maximum funding for 4 years will unlock all the roller coasters and gentle/thrill rides available, along with some shops and stalls. Shops and stalls variety is an important factor in a 4-year scenario because the lack of food variety may become a negative effect over the time, with the "Worst Food" award, that if gained will act as a counter-ad campaign.
Reaching the guest objective isn't hard at all : players still short of guests as deadline approaches should reduce their prices for rides (not for shops/stalls) and launch a couple ad campaigns to push the numbers up. Turning the flat rides near the entrance free, would also help in holding broke guests in an extra couple of months.
Pacific Pyramids — finished by Hadesengel.
Pacific Pyramids — finished by Felipe717.
Pacific Pyramids — finished by Zachl1226 (version #1).
Pacific Pyramids — finished by Zachl1226 (version #2).