Where to place my two channel in new room?

Typically one will create an equilateral triangle of 6 - 8’ away from the back wall. So I would start three feet from the short back wall and in 3.5’ from side walls. This should work great as a starting point. Not having a wall behind the listeners position is great, no problem with reflections behind. Some side wall treatments may be required. Sounds like a good space. Do not position equipment between the speakers (only amp). You want direct lines behind the amp and off to the side for your components.

Check out the AM Acoustics room mode simulator.

Normally you go with the speaker facing into the long part of the room then toe it in 

go to the Cardas cable website , they show you how to set up your room .

Length wide with your seating wherever the Bass nulls in your room sound best. I have a 30 x16 , I have a similar situation ,my ceilings are only 8 ft high.

Mcintosh C2700, Mc611s Rose 130 love loud clean with huge dynamics! 

Room is 43' x 15' I need to figure out how to post the blue prints. 

Thanks

Yes room dimensions and your other equipment and musical preferences.

Did you draw it with invisible ink?