This is a remix of http://www.thingiverse.com/thing:376267
I wanted a tighter fit on my own A1200 as when I printed the original part in Formfutura White ABSpro it fit ok, but there was a bit of movement and rattle. Perhaps there is some shrinkage on the ABS that causes this, if printing with PLA you might be better off with the old part.
I used Blender to increase the size on this.
This new part is a fraction larger to allow for shrinkage, dimensions of old and new part below:
It printed well for me at 0.1mm and 90 percent infill on my Ultimaker 2 Extended. I used 90 percent infill as there seemed to be a big print time difference between 90 and 100 percent.
I used supports on both ends of the trapdoor to allow the clips to print without turning into a mess.
Some light sanding on the clips on both ends to smooth them out a bit. 5 mins work at most.