Hey Karl who is it being built for? Surely not Geoff.
There is some info at www.s13rally.com They look like they make a pretty good rally car, with heaps of performance parts around, and lots of knowledge from the drift guys on what needs strengthening.
Which do you think would be better the Silvia or the 180sx? I suppose the 180 has much better access into the back for cage building and packaging, but the Silvia might be a bit lighter with less glass, and no pop up headlights.

I will be watching this with interest.
Wavey.