make sure the motor bracket is in the middle of the pole ie havin an imaginary line in the middle of bracket and pole
as you start to tighten the nuts you will pull the bracket what ever side you tighten up,make sure you do it evenly
also make sure the dish is in center with motor arm ie same as bracket and pole
edit also get a sat beeper from argos about £15 then when you set it all up take the meter back to argos
I like your thinking here ill be at Argos tomorrow