Trying to work this chassis through... The other way you can build this is by putting the ERLL in the side torso and somehow forcing it to be the high mounted one...
To get your ERLL at the top hard point, put the ML on first, then the ERLL. EDIT: removed part of my comment. Looked at build wrong.
Interestingly, this build also works with the stock engine and armor. All it needs is Dual Heat Sinks, making it a good choice for players who don't want to invest in a new XL engine yet. I was even able to add AMS, but a heat sink and a 3rd JJ are an alternative. I prefer a Large Laser for the shorter duration, especially since all the other weapons have considerably shorter ranges as it is. The next step would be to swap Ferro-Fibrous for Endo-Steel for another heat sink. After that you could consider an engine swap.