looking at the texture used; so, originally different segments of these images were different 64x32 images. the ripper supplied those images, but they are not used in the obj. instead the ripper attempted to compile those images into a single 1MB 1024x1024 image (with really bad use of wide margins, wasting precious texture space! and causing visible edges).
the scene model is comprised of an object with 4 flat squares comprised of like 20 separate meshes each, totalling exactly 256 polygons, or 0.25 MB so the entire scene costs 1.25MB of RAM on a system that had a default RAM of 4MB, 1KB of which was used for system overhead. Not counting collision geometry. I'm guessing it was around 1.5MB total without characters and props.

Honestly, this space was a poor use of memory. 256 polygons? you can do alot more with that! infact you might be able to have basic outlines of the visible elements with that, then they would have saved on memory for collision bounds.

It might be useful to make a better composite image without wasted texture space. if I make modifications I may upload a revision.

I made revisions to the texture and will upload it on the original model. I made a 4 quad model to test it on and it worked well, however on N64 I think the problem they ran into was that the maximum texture size was 64x32 and the system only allowed tris not quads this resulted in the 256 poly object.

Man I wish someone ripped the Collision Model for this area, I kinad want to recreate this but I don't have anything to use as reference.