Hey mate,
I had one of these brand new years and years ago as my first nitro, gx.12 engine with single needle adjustment, side muffler that exited through the chassis, single gear, such a basic car, but so easy to run/tune/maintain, i LOVED it! As you say, tought to break! mine never died, the engine would still run after at least 6+ years of harsh inexperienced use. Mine came with the 206 rally shell and 5 spoke design wheels I believe, nice to see one about! hope your plans go well with it, be good to see.
Dan