I don't believe they had plastic but I honestly can't remember. From how much the darn thing weighed, I'd doubt it.
I know they were built from the mid 80's to early 90's and were the model before the 455. Had the Yanmar 3 cl diesel and had hydrostatic transmission though it was only hand controlled. No foot controls.
I remember the mower deck alone weighed almost 400 lbs. It was a beast.
