thanks guys.
As usual, I'm late with my build report
I added the aeration at the back. This part is basically made with a frame whom you "wrap" the side, then glued to the "base". Nothing hard but no place for adjustment. I focused on getting top and side aligned, this end with a little gap between the side and bottom of the frame but nothing to noticeable.
Next parts made was the two sprocket gear. Again nothing hard, just time consuming
even there's lasercut, you have to cut the paper part too (for the size) ; now I paint with tamiya xf56, not only is faster but it act like a mastic and smooth the difference between paper and cardboard
added few bolt, mode to glue...
now I'm working on the rollers. Tracks are made for this model I have to add then soon in the build because I don't think It can be added after the bumper.