Who wears black ASU pants with two gold stripes?

It's actually the standard for GOs.

It is a common misconception that GOs may design their own uniforms. Only the Chief of Staff of the Army and former Chiefs of Staff of the Army may prescribe their own uniforms, this is according to the current AR 670-1. The misunderstanding about all general officers being able to prescribe their own uniforms comes from previous versions of AR 670-1 that had additional verbiage that "Generals of the Army" may also prescribe their own uniforms. The term "Generals of the Army" refers to the rank of General of the Army, i.e. 5-star generals, not all general officers in the Army.

Thanks, been out a while. I remember GEN Westmoreland wore an air force style short sleeve fatigue shirt when he would come to visit us also a brim hat, not boonie, with brim turned up on like a tricorner hat. Also he had jungies with WESTY on name tag. I was a PFC at the time working in BDE TOC and was told the GOs could wear what ever pleased them. He was MACV CG at time, not CofS. I not have a pix handy with the SS air force style fatigues.

CW4 Keith Dolliver Chief, you beat me to the comment. No excuse but one alibi: I find Rally Point to be unwieldy using an iPhone. Took me five minutes to find my own comment and still couldn't figure out how to delete it.

AR 670-1 “Applicability” changed the ability of General Officers to design their own uniforms, sometime between George Patton’s time and 1984. It was changed to “ It does not apply to the Chief of Staff of the Army, or former Chiefs of Staff of the Army, each of whom may prescribe his or her own uniform.”
Not sharpshooting but we cannot let senior leaders to go crazy and dream up some Halloween-like costume!