22 mid, saddle pack \ losi short lipo, side by side mod i did yesterday. cut the plastic sides to fit 2 saddles side by side, then shave off chassi edge, make a flat spot so the edge not hurt the lipo. make a battery brace and mount battery posts. space between low profile servo and lipo is now 7 cm. you mey want to fill up under lipo with something ca 2mm plate becouse lipo is higher outside on plastic\chassi side than in middle. you can mount electric where you want.
one downside is that orig losi body wont fit due to lipo is higher than plastic sides. so a FTW vane body is best choice.
http://www.avidrc.com/product/18/bod...es-by-ftw.html