With the amount of time you've taken off, I wouldnt go past 750mg on the test. I think you will do great on that and anymore would be a waste. Personally, I've never had luck runnign deca with tren together. Progesterone levels were just too high for me, but I've heard of it working for some and that those guys have had good experiences. You might want to throw some caber in there at .5mg 2x wk, or at least have it on hand, in case you need it. I've also heard some data saying that ghrp can cause a spike of progesterone, so since we're already on that topic, I'd keep an eye on that. 

If the possible issues with a deca/tren combo isnt something you had thought about, maybe consider using NPP for the first half of the cycle and tren for the second. That is a cycle I have run and found it works very well for me.