Replacing Martin Logan Sequel panels

I recently purchased a pair of Martin Logan Sequel's from a local dealer for next to nothing, the reason for the insane price was the dealer informed me that one of the panels' output was fading due to age. Well, I bought them anyway knowing that I could get replacement panels from ML at any time. I ended up getting a pair of replacement panels from a fellow Audiogon'er and began to install them tonight. First off, and I consider myself to be fairly intelligent when it comes to this hobby, but the panel replacement was and continues to be a bit frustrating. I replaced one panel tonight and plugged the speaker back into my system expecting to hear a difference and I got one. IT WAS WAY WORSE! Talk about muffled, I'm getting sound, it's just foggy and muted. I followed ML instructions to the T however it sounds like I did something wrong. The only thing I can think of is the pigtail connector that runs from the panel to the crossover box. I had to (because ML doesn't ship new panels with the terminations for the crossover) remove the old panel, jimmy the wires from the termination (forgive me I have no idea what it's called. It's a little white box that the three wires fit into via a trio of metal clips. If you know what these are called please let me know) then replace the wires with the wires from the new panel. Removing old wires from their terminations proved to be difficult because the people over at ML seem to love solder. So, I'm thinking because those connectors are A. old, and B. crudded up with old and excess solder it's to blame for my less than stellar sound. Also, my bass has become very very boomy since replacing the one panel. I hope someone out there knows what I'm talking about and might be able to shed some light on my troubles. They really were great speakers and I couldn't bear to think that I damaged them, even when following the directions to the T. Thanks everyone.