get the 400 ex rear shock, i have an '05 trx 450, harder to mount, had to cut the one flange off that the front of the plastics bolt to, the rezzie is offset, the 400 is the same shock but straight rezzie, less cutting, and i'd get a newer 400 shock over a 20 year old 250r shock anyday
and spend the $150 - $175 on some works fronts, you'll think you're on a different bike, yeah, that much difference, worth every penny