Those are good photos. I'm going to say that this is a 10T but, at some point it was missing parts or a previous owner wanted to do some upgrades and installed T2 arms, front shock tower, shocks and mounts. The steering knuckles appear to be correct for a 10T, however, they would have originally been white. Associated did offer optional black plastic parts for the RC10s and RPM made a few pieces too. I've switch most of my car to black plastic with RPM rear arms specifically for RC10s. Anyhow, that piece in the last photo is a "upper deck" or "chassis brace" from another vehicle. Maybe the T2 / B2, I don't recall what they look like. But, it won't fit onto this truck. One later generations, this is what replaced the aluminum tubes when they switched from aluminum pans to composite chassis'. I also see the original style front arm / shock tower mounts in the center. Those are RC10 rear arms but I want to say those are buggy arms, truck arms might have been a little longer. Hard to say from a photo.
It's a customized RC10T. Unique but whoever did the customization apparently stuck with T2 parts which isn't necessarily a bad thing. It hurts collector value but, it makes the truck drive more like a modern vehicle while retaining some vintage appearance. Cool!