This scenario is not really difficult actually. You have enough space, and getting 1,000 guests in 4 years should be no problem, especially if you successfully completed the previous scenario or even Evergreen Gardens which has the same objective and also starts from scratch besides the path system.
You might delete the scenery around the map for extra money. Although, the scenery does add for the Excitement Rating of your rides and also makes the park more beautiful, so keeping the pyramids and stuff is actually not a bad idea. In spite of that, you should have noticed that there is a path which goes underground from the top of the dunes to the sphinxes area. This path is completely unnecessary and must be deleted, as it adds nothing to your park infrastructure-wise and it has no other functional purpose, so get rid of it right away.
You can start off by placing some flat rides and a small roller coaster (like the Steel Mini Roller Coaster or a Steel Roller Coaster it you set it on powered launch mode (you don't need to build only Shuttle Loops as it's a custom-made ride and you'll not develop any of coaster building skills with them (or just for the sake of building your own rides and leaving the "Shuttle Loop easy money-making strategy" for a while!))).
You should start developing your park in the first half of the land (until the dunes) and, then, keep expanding until you've filled the space available. You can buy extra land cheaply and your park could get way larger, but it's not mandatory as you can very well focus on nicely developing your original land throughout the 4 years. Keep in mind that you can and should make use of the underground of the dunes area.
Have in mind that if you research at maximum funding for 4 years you'll have researched all the roller coasters and gentle/thrill rides availabe, so if you do this you'll also get some shops and stalls. Shops and stalls variety is an important factor in a 4-year scenario because the lack of variety may become a negative effect over the time.
You'll probably reach your goal sooner than expected and if you keep an eye on your park and use the general strategy you've acquired so far, the scenario's completion should become easier as it goes. If you feel you may run short on guests, just open up an advertising campaign or two to bring some more guests in.