my trex 450xl leans slightly to one side while hovering is this normal or is it because of component placement??ie more weight on one side

No - it's the torque of the rotor - the fusealage has to be off-level in order for your heli to hover in place. If the fuse were flat, it would drift off hover.

Translating tendency. Its the tail rotor pushing the helicopter sideways, to compensate you need a bit of right cyclic, even the full scale heli's do it.

If the main rotor is left hand rotation (counter clockwise) the heli leans to the left to correct it.
All of the controls on a helicopter interact constantly. For example you add power, that makes the tail want to turn, you (or the gyro) corrects for this now you are adding right rudder so the heli wasnts to translate left even harder so you need more cyclic to compensate which requires more power...... you get the idea.

When I first built up my T-Rex I had some of the lengths wrong in the ball links which caused my heli to hover at a crazy angle... it looked so wrong!!!! After taking another look I found I had miss matched lengths in the links etc... After fixing it up it now hovers levelly... Hope this helps!

WHEN I FIRST TOOK MY TREX INTO A HOVER IT LEANED TO THE RIGHT BUT STILL HOVERED CORRECTLY. MY TAIL SERVO WAS ON THE RIGHT SO I ADJUSTED MORE UNDER THE BOOM AND WALLA-ITS FINE. HOPE THIS HELPS. MIKE

If you have a simulator, the sim helis do the same thing.

I HAVE THE G3 AND HAVENT NOTICED THAT. I COULD BE WRONG THOUGH. ILL CHECK AND GET BACK TO YOU LATER. MIKE