Easier parts printing for XY lowrider (Q43062)

I changed the design of some parts of this low profile design in order to print it with my MB. Although I had no problems with most of the other models, some of them were impossible to print for me. Usually he nozzle was always separating the part from the build platform soon or later. Sometimes I decided a different approach in which I printed the thing in a different position, in two separate prints, and then join them with bolts. Other variations are small, for example the fact of hiding the bolt's heads inside the plastic in order to not interfere with my ABP.