So far so good actually. Yes custom motor plate. All in took me about 2 hrs. Diffs are holding up well. Its doesn't have as much power as brushless. It seems to be just right. Not too much power so it destroys everything. Ill keep you updated on the durability. I know even the stock 380 motor can strip the diffs so i dont think its going to last all that long. But we will seeLooks like a custom motor plate. Hows a 540 motor on the stock diffs? I went with what I thought was a mild brushless 2040 3800kv motor and stripped a diff at $25 a pop I don't think its worth the risk for most on a $100 rc. Some like going without gear covers but I prefer them the ruckus gear cover seals up pretty good. Going big maybe cheap for the motor but could end up being big on the repair bills.
Just my thoughts on 540 motors on small scale plastic diffs.
I have a older 1/18 Ruckus the earlier versions did not have shims when I bought a newer diff they have shims in them now.If you're not going to shim the diffs on the Ruckus,Torment, Roost then stick to the stock motor, adjust the slipper and run 2s.
It's a name brand hobby grade RC for $99 or under and when you look at it that way it performs well.
Instead of this motor upgrade you can buy a whole 18a brushless system from amazon for $30 and it should just swap in without an adapter. It'll probably outlast the ECX and you can put it into another car down the road. It'll run 3s but unless you're really careful it'll break stuff.
I'll report back if it doesn't fit.