Inside a barn at the end of that little offshoot road on the map. Beware rampant cattle, they trample for laughs.
Take the metal staircase up to the second floor of this unfinished concrete building.
In a little tunnel just off the road.
Among some trees on a cliffside that juts out over the water. Take a moment to enjoy the views, or steal a boat.
This part is on the structure of a bridge. As far as I'm aware the only way to get it is by air. Either by flying a helicopter right up close, or parachuting in (something like this).
Another inconveniently placed spaceship part. It's on the rocks under the bridge, next to some rapid water.
This part is up on a mountain ridge. The best approach is via helicopter. Try to spot the part before you make your landing, as walking around on the mountains is annoying, and potentially fatal.
On the western bank of a river, just south of the bridge.
Underneath the wooden shed / bridge, between two concrete supports.
On the porch of a cottage near Larry Tupper's barn (bail bonds mission).
Languishing in the dust, below road level.
Inside a loving community where aliens are welcome.
Underneath a fine boat.
Climb the ladder up to the highest walkway of the westernmost satellite.
On a large rock in Senora National Park.
In the water behind The Boat House. The part is not very far out, but you do need to dive to get it.
In the grounds of another alien welcoming commune.
Inside a boatshed just off the water's edge.
In a farmyard among the cows.
At another farm, in the barn.
In the alcove where water meets land there is a dark cave. You can find the spaceship part underwater. There's also a paper scrap in this cave if you're looking for them.
On the rocky beach in the Tataviam Mountains.
At the end of some waste pipes in shallow water.
Underwater, beneath the wooden boardwalk.
Another underwater spaceship part. This one is wedged in a corner, right up against the dam wall.
On top of a little white tower overlooking the resevoir. Use a helicopter to get up there.
Up on the first floor at Galileo Observatory, on the ground next to the eastern dome.
In shallow water at the foot of a waterfall (you still have to dive for it).
In Marlowe Vineyards, between the rows of vines somewhere near the middle.
At a home on the hillside, in the back yard.
In a little cave just away from the stream.
Inside the grounds of a large property. The part is at the base of a tree, near a small paddling pool.
At Los Santos Golf Club, on a little island in the southern-side lake.
In Richards Majestic movie studios there's an area which looks like a regular street of houses. The spaceship part is on the roof of one of these.
On the rooftop in an empty swimming pool. Best to use a helicopter to get up here.
Rockford Plaza has a small green area with a road going around it. The part is in the grass. This area is raised from ground level, so either follow the road or land a chopper up there.
This part is deep underground. You need to gain access to the sewer system (used in a previous heist). The sewer access point is marked with a green pin on the map above. Once you're in, head towards the subway system where a lot of construction guys are hanging out.
On top of the Penris skyscraper. Use a helipcopter to reach it.
In a colorful alleyway between Bean Machine and SND. Textiles.
Use the metal walkway around the dam and hop the fence onto a concrete pillar.
In a hobo sanctuary underneath Olympic Freeway.
Head round the back of a bar called Liquor Hole, there's a ladder leading up to a huge billboard, where the spaceship part is waiting.
On the roof of Central Los Santos Medical Center near their helipad. No need for a chopper of your own, you can use the ladders to get up there.
Inside a green freight container just off El Burro Boulevard.
On the eastern side of that tiny island.
On the beach, right next to a sewer outlet (hygienic).
At the base of some kind of modern art sculpture / climbing frame?
On the pipe that connects those two domes. Don't look down.
Underwater, just off the dock.
In a fenced off area at the edge of the airport. You'll attract three stars of unwanted attention when you get in here, so move at speed.
Take the final part back to Omega's trailer for an... impressive display.