Yep, you're nuts.
I'm planning to drop a big bolt cab and fenders on a P30 frame. The P30 track width is about 8 inches too wide, and I haven't decided if the answer is to narrow the track or widen the fenders.
I'm also thinking I need an extended cab, but that's making it longer, not wider, so I'm not nuts like you.
Tommy's truck looks like he used a Suburban roof, and maybe second window. Does anyone know the details of his modifications?