As with the front space frame, the Fujimi kit mimics the rear chassis of the 917 K well. The downside is there are lots of flexible little struts needing to be put together just right.
The only issue with the HRM resin bits was a couple of instances of the cyanoacrylate glue being reluctant to join a styrene strut to a resin crossmember. I don't recall this being a problem in the past, but then I have rarely needed to join resin to styrene. Maybe epoxy would be better here.
The complexity rivals Tamiya's lovely 300 SL chassis; the Tamiya effort was easier to put together because the styrene was somewhat stiffer (perhaps the specific styrene formulation, perhaps the struts were a bit thicker), and because of decisions made by the mold maker as to which sub-molding should include which specific strut. In any case neither is for the faint of heart, but the 300 SL is easier to get right. (See pics of the 300 SL here).
One issue, as always, is how much of it all disappears behind various shrouds or other "sheet metal" bits. For example, most of the spark plug wiring is invisible once the air cleaner assembly is added to the top of the injection stacks. A shame, really, given the effort on the ignition, but hey, you and I all know it's there, so that's sufficient.
All in all a very challenging kit that will reward a seasoned modeler, but will frustrate a beginner. The HRM motor does not add any complexity as everything fits well, but be aware the instructions are quite terse and require some significant study. Access to reference material, online or otherwise, will be useful. I had a look at the instructions for their Cheetah and can imagine a careful pre-assembly will be needed to be sure to get the sequence right.
Next: put in the dash and a few added bits around the rear (inner fenders, rear lights), then wait for the paint on the body to harden enough for some polishing.
It's coming together. Stay tuned!