Matchless can handle my 45'er w/tow with ease because of the way the "parking lot" is arranged and is all drycamp. Using Matchless you will have a backup if BabyDoe fails you. I can't recall what I've seen in BabyDoe but Silver Dollar and Molly Brown I seem to recall seeing good sized A mohos (like low-mid 30s). I know my 45er will only fit (or can even get to) Matchless - the first CG off Turquoise Lake Rd. Typically, arrive on a Thurs and you'll almost always get a spot. Starting on Fridays first come goes really fast in the summer.
SugarLofin private CG at the entrance to Turquoise Lakes is another option and reserve-able. It isn't NFS, but OK as far as privates go. Nothing great except the location. Make sure they do not put you in the small loop "behind" the office - the entrance turn to that loop are tight and low trees. Make a point to NOT stay at the Corral or whatever it is called RV park in town. It's far far worse than a dealer lot line up.
Book 4July NOW. The fireworks show in Leadville is positively worth it (both in the air and on the dry ground and the people too) and then do dinner at Quincy's. You won't go wrong with their 1 item only menu (prime rib fri/sat, filet rest of week). Superb for superb low dollars. I guess you do one thing and you figure out how to do it right! Manuelita's Mexican across the street is amazing fish based Mexican. get the red snapper platter. Wow. And at 10,500 ft elevation as far from the ocean as you can get too!
Lance Armstrong and maybe Floyd will be in town in August for the Race Across the Sky!
http://www.leadvilletrail100.com
Off Halfmoon road as you enter the NFS land are several boondock spots I can even get my 45er into. Not overly easy, but doable. Here's some GPS coords (WGS84) for these spots. Free too. Many more along the road in that area will easily fit you. But, the Halfmoon road area can get very busy weekends with hikers going to Mt. Massive/Elbert.
39.19353, -106.3816
39.19118, -106.38105
39.18462, -106.38451
39.18287, -106.38508
Google Earth is the best way to scope out CGs. I use it all the time in planning where I can get my big long 45ft arse into.
Good luck and happy Leadville.