The concern with a top deck post set-up is that as the chassis flexes, the steering would not be very precise as it would induce "flex steer".
Honestly, for the time being, we are not planning on a conversion. If we were ever to do one, we would make a chassis for it. If we can find a company cut a limited number of chassis, then we would consider it, using perhaps the XRAY parts. We would just need to get the parts re-anodized in black or blue to match.