Wasn't the picco mount included and had a place to mount the pivot like the stock mount? The carriage was a bit wider to fit the engine in there and if I recall, it was also fixed, so you couldn't adjust the mesh. It would only work with stock gearing, or you had to increase the bell/decrease the spur to change it.
I had to get creative with my new era style mount/linkage:
That was the first install. But the wire would bend.
Then I did this:
I couldn't find any wire stiff enough to not bend if I had a TRS on it. So I doubled it up, wrapped it in copper wire, covered it in flux, the soldered it.
The new era mount came with a little block that screwed into where the stock TRS went and the wire would go through it as a guide:
But it left very little wiggle room for movement to actuate the throttle, so if the wire bent at all, I couldn't get WOT. If I ran it too straight, it would hit the flywheel or the new era roll bar. I've had it like that for 5+ years.
I had to get creative with my 21TM install in my other revo as well:
The integy roll bar/engine protector was in the way. It's been working fine like that for 3 years.