What is too much fermentation?

How are you bottling? Bottling bucket?

Best way is to cold condition the carboy at ~34 F for a few days in a chest freezer or kegerator, then transfer out of carboy via auto siphon racking cane to a bottling bucket or keg.

 

It should be fine if it was initially brewed properly. The extra time wouldn't have hurt it. In fact, if you've got all those lees at the bottom that's great because you'll get a nice clear beer. So, as hoptualBrew says, use a racking cane; and simply try not to move it too much before you rack it. Also, I'd leave a little behind rather than trying to get as much as you can and sucking up that old yeast, protein, and hop residue.

 

You can't have too much fermentation because the yeast do their job and when there's no more work, they 'quit'. I wonder what John Palmer would have to say about your beer sitting on the trub for two months though. I'd give your beer a taste via wine thief and see what you think. Sounds like you've gotten ahead of yourself if you don't know how to rack your beer out of the carboy without picking up the sediment. Do you have an auto-siphon?

You first effort sounds amazingly ambitious. Hope it turns out well.

 

I wouldn't fear 8-10 weeks in the carboy. If anything, I think you will get a better result for having let it sit for a nice long period of time. Most new brewers are too anxious and barely wait long enough before bottling and subsequently opening the bottles too soon, too.

 

The only thing I would be concerned about is oak chips for 2 months. You might be looking at a tannic mess, but hopefully not.

To bottle, racking cane/autosiphon to a bottling bucket being careful to stay above the trub when you rack. Determine your priming sugar after you see how much is actually in the bottling bucket. This prevents overpriming if you end up with significantly less than expected. Use a calculator to determine the proper amount of sugar given the volume (something like this http://www.northernbrewer.com/priming-sugar-calculator/) You might also check out How to Brew (http://www.howtobrew.com/section1/chapter11-4.html)

 

Besides the extended time on the oak per the post above, if you really have 3" of trub at the bottom, there is a chance that your beer might have picked up a slight vegetative taste, but you're at a point that you need to package it to find out. Keep the bottom of your racking cane or auto siphon above that trub so that you leave it behind. You can monitor it by watching the clear tubing to see how clear the beer is when it passes into your bottling bucket or the bottles. But for only two months I doubt that either issue is justification to dump the beer.

 

You are fine other than using oak chips for 2 months.. Might be a bit over oaked depending on how much you added.