So this is the main reason why I bought the pop scanner which is to capture complex mechanical geometry for processing into CAD. So far it’s going quite well, even though I am scanning with ‘features’ as the dots are still in china somewhere 
I could take manual measurements here but getting these compound angles is so much easier with the scanner. Parts are aligned and trimmed in Blender, traced in Solidworks, checked and then put onto the assembly (no I haven’t done these yet).
Geometric shapes are quite hard for the POP, it gets a bit confused when resuming a scan and sometimes puts things in the wrong place, I recommend making a shortcut to the data folder and make copies when you fuse the points to ensure you don’t lose data, but it is well capable of the task.
Great, did you spray something on the frame to scan?
That looks like a Lotus Esprit chassis! I have it’s sister-car, a DeLorean. Similar styles of chassis.
You might be interested in this restoration series: https://www.youtube.com/c/GeorgeKarellas/videos
I’ve been working for probably 10 hours total over a few weeks on trying to get a good scan of my DeLorean’s frame and engine bay without much luck. It’s getting better, but you’re right - the scanner does not like scanning areas that are geometrically similar. For example, if you try to scan a pipe, even with markers, it will often times “run off”. And if you move off of the pipe and back on, it won’t know what area of the pipe you are on, even if you use markers.
My suggestion would be to get those markers, put a lot on, and then do scans from one area that has a lot of unique geometry over to the other area with unique geometry. Then scans of each of the ends of it to get more detail, then combine them all in Handy Studio.
On Youtube I looked for some techniques to scan objects like similar faces, I saw this technique that must be applied. In oratica you add other objects on the plate so that the scanner also follows those and manages to scan the object well with all faces the same.
Bare steel, and just crank the gain up 
Yeah I used to do that trick before my CMM days, esp on curves where dots dont behave so well.
What’s tricky here is when you pause and resume, the software grabs a feature like a hole or a tube and gets confused, I’ve had tubes growing out of all sorts of areas before having to hit the undo button
Yeah we have chatted about the DMC12 before 
TBH I’ve just used the scanner for the compound areas I cant easily measure (cant be bothered to LOL), or just to let me know I am on the right track.
Most importantly I have the jig dimensions from the service manual so I can triangulate a lot of this and fill in the gaps. I’ve scanned this way for years, using a hybrid method and imo its the best way unless you have access to a CMM.
Even with dots and gizmos I think there is too much drift with POP - I don’t know what the drift is but it would be interesting to measure because I have had tubes come out a little bent before (also see the bumper thread I did). I use it like I would use any tool, it fits a specific job.
HAH!
Clearly I don’t come on this forum very much - I didn’t even look at the name I was so enamored by the Lotus frame. 