Honestly - I get why you are asking having waited 16 years - but all of the units you mention are great. With 16 points I assume you are not a resident. So if you are going guided, don't worry about how much wilderness there is in a unit - just find a good, reputable outfitter with a good track record and book it. If you are going DIY you need to consider how much land is available to hunt outside the wilderness and whatever unit you pick, you need to make sure you are in great shape and have at least 10 days to hunt. No one goes into any of the units you mention assured they will see a 350 bull - but there are a few in each of them. All of these units are great but you most likely need to go in deep and hunt high. I hunted a Park County unit 4 years ago. Packed in 4 miles before I started hunting and 3 days later I found myself in 8 miles before getting into elk. I ended up weeding through a few bulls before taking a nice 6 x 6 that I was happy with - but he was not 350.
Luckily I invited a strong young lad from work to go with me and my son lives in Bozeman and is in great shape as well. My son talked a buddy into going with him to help me pack him out. Me and the young guy from work got the bull 5 miles from the trailhead before my son and his friend showed up. We all took a heavy load and with 4 packs we brought him out. Hotels, food and drinks on me once we got to Cody!! The next day the guy from work and I had to go back to the unit and get our camp and pack it out. We had an absolute blast - but we were all in good shape with good mental stamina.
I guess I just brought up another good point. Whatever you do make sure you have a good plan for getting him out. We had perfect meat hanging temperatures and basically dropped everything and started packing once the bull hit the ground. Still took us 2.5 days to get the bull to a cooler. Unless you have people like I did, you will need to hunt closer to the trailhead, have Llamas, or work out a way for horses to pack the meat out.
Good luck - as long as you're in shape and have a good plan you should have a blast no matter which unit you end up choosing!