Those Opel motors are really strong, i wont deny that but i would not put one in my 200sx no ways, i hate to mix brands, i would put in an SR20 one time, then you dont have to modify anything on the body to fit it, and those 200ts engine parts are harder to find as far as i know compared to sr20, and aftermarket parts are so plenty for the sr20.
And what gearbox will you use on a ts motor to get it rear wheel drive? can you pop a rwd box onto the bell housing? sounds like too much chopping and changing to me.