After the issuse faced with openscad, I turned to the one place to save me google. Luckly it turned up a tutorial on how to use meshlab (an open source modeler application) to import multiple stls and move them into position. After using the teadios gui and very unstable software (I had to repeat quite a few times with 5 or 6 crashes) I had multiple servo brackets in one stl file ready to print!!!
This is the first large job my printer has done, the print file generation too around 30mins and the print time was due to take 10 Hours!!!!! So I setup the printer and headded for bed, dreaming of the nice new brackets awaiting me tomorrow morning.
I got up for a drink of water during the night and went to check on the print. The print had torn itself appart, the parts had warped so much that they were much higher than the nozzle. Then when the nozzle had tried to transition from one bracket to the next it had drivent the nozzle through the warped plastic and ripped the bracket completetly off.
With 13hours still togo all is not yet lost. I will switch to manualy building some metal brackets and ask for a favour on a friends laser cutter. Hopefully still leaving enough time to code up the walking.