With the adult sized pack you get the extra weight which can only be good.
How I managed to get it done was build it in mid I have a low profile servo which helps a lot, they aren't that expensive used so worth it to get the extra space.
I used the tank stands from my nitro spares and put them in the holes that were already there for the battery brace
I then cut out the x in the rear chassis brace/esc mount
After that I used cardboard to get a rough shape of the plate I will use, I hade 3/4mm plexiglas at home so I used that ( I may make a carbon one later or a shorter brace)
Cut it to size drilled the holes used some thumb screws and done
I may move the esc back and RX foward so I can get a fan on it. It fits now but rubs on the shell.
I drilled out some holes in the shell windscreen that are spot on to get some air over the esc
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