The channels look centered over the core of a cpu so I wouldnt think this would be much good with tecs?
If you put 2 more holes on each side, you can leave a 40mm gap between them so you will still have space for tecs
For the lid dont use accrylic. Use polycarb if you want it transparent or derlin/polyethyelene/metal if you dont. Polycarb is good but its not perfect, some people have had problems with it.
I think JFettig is right, you should a couple more holes to hold the lid better.