quantum,
2big is correct....a couple of other "threads" on suggestions for underwear and various success (and even some non-successful) stories too, I would reckon.
It's all interesting reading. Here though, is an idea or two....
You are currently close to catching up with me in size...both height and....well, -- the other, too.
Since you and I are near the same size, you may want to try boxer-briefs. Boxer-briefs have filled the bill for me when regular boxers didn't quite conceal (as I had wanted) or the occasion demanded "more control" and "less show".
I tend to deal with a longer flaccid length than you cited and boxer-briefs have worked fairly well for that preDICKament (forgive the pun)-- most of the time.
Yet, boxer-briefs may NOT be the perfect answer, either. But, they do seem to "keep the gear confined" pretty well with that built-in "pouch feature"...(should help with testicle support) and may even help with the erection-projection which you mentioned...at least a little bit.
A few posters in the past have opted to mention a jock-strap worn beneath boxers as well... (where you would learn to position the penis "upward" for the most part), but this is not going to be the answer for many unless such a strap is special-made to accomodate the size and allow for comfort. 'Seems to be even more of a challenge to find a source for special-made support straps...particularly here in the U.S..
As to pants (if you don't want to show a bulge), stay away from the lighter color fabrics as well as the "flat-front" slacks. Pleated slacks tend to help conceal a bulge pretty well over flat-fronts.
Jeans.... are another whole story altogether. I've yet to find jeans that don't show at least some bulge...some designs/brands more than others. I suppose there are occasions whereby---that's fine and dandy...you can get by with it. ---------------- I know I do!
--The things we guys must go through to "keep ourselves together! ;D
I would encourage you though, while you're so admirably trying to not flaunt what you've got, don't become overly ashamed of yourself either. There are going to be inherent limits as to what you can do to hide the facts. Like many of us have finally learned, comfort should be a factor in your clothing decisions... particularly so in underwear.
Enjoy being a larger man. Accept it with pride.
And, try not to fret over it.