That looked quite nice on the pictures. However that is lots of work and takes skills to get smooth surface.
If you use 3mm thick ABS plastics that has etched surface you can make this kind block in a hour if you have praticed or about three hours if its your first time:
Upper block from behind...
Total looks of the car.
Beginners guide:
1. To shape the block first cut right size paper/carboard block
2. transfer the lines to ABS plastic with pen marker.
3. draw the line with sharp knife plastic on the floor. Once is enough.
4. Bent the plastic and it will break along the line
5. fit to the car and fine tune cutting off small pieces with knife. 1mm is easy but up to 3mm if you have sharp knife and right technigue.
6. mark ziptie positions with pen marker
7. drill 5mm holes
8. Make about 50mm hole for outside temperature sensor
9. Install and enjoy
I just measure and build without template and it looked like that with first try
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