Well as I said I seem to vaguely remember a nomad for 58. I recall the 55 and 56 very well, course as pointed out they stood out with obvious trim.I'm certainly not disputing the existance of 58 Nomads.
I owned a 55 Chevy wagon but not a Nomad. I changed the 235 six out to a 64 327 with 202 heads, small solid lifter cam etc. In 55 with the 235 stick the wagons rear gear was 4.10 which I left in place. That car with the 327 and mild work over, 4bbl, dual exhaust hauled serious butt, it would definitately sit you back in the seat when those secondaries came in..