Chad, welcome aboard, and everything's cool.

One of the issues you have with advice is the current fish and fish types. That makes it hard sometimes to give good advice, which is what you want and need.

If it was me, I'd get that structure in the pond as soon as possible, and give it a good soak before I stocked anything. If you do still have larger number's of CC, that will give any BG you add a place to hide. I would continue to fish for the CC and any possible LMB to get a better feel for the numbers already there, and get them removed.

Here's a thread on structure and cover from the PB archives.
Structure and cover

As far as transporting BG from the creek, if it was me, I wouldn't do it under any circumstances.

LMB are easy to identify, so if you do move some to your pond, they or may not survive the move, but they probably wouldn't hurt the pond. But, they'll aggressively eat anything else in there, including future LMB fry stocked, so you would probably lose quite a bit of those.

Here's some pictures of Coppernose BG, which is what you ultimately want.
Coppernose Bluegill

As far as trophy LMB, it's recommended that you stock 1,000 Coppernose BG for every acre of water. For trophy's, you're probably talking 2-3,000 per acre. That's 6-9,000 CNBG for your 3 acres. I would give them until late Fall at least, then stock your LMB at no more than 50 per acre. Maybe half that for trophy's. But, my limited experience has been that lower stocking rates for LMB, and higher stocking rates for CNBG, can make the LMB far more difficult to catch. LMB stocked at lower than recommended rates will swim around like Blue Whales eating Krill. They'll just swim and eat. It can make for great trophy's, but it can also make them harder to catch.

So, if you read all this, remember it's just my thoughts. Smarter guys than me will chime in also. Good luck, and post some pictures of the pond. We love pictures.

AL