a lot has happened here Paul!!
congrats on the CLK55 donor car, its been a long time coming!!
Just curious to know if that CLK55 rear subframe will fit?
I would run a separate trans oil cooler as well.. the one in the rad is sufficient, however an aftermarket cooler core would probably do more good to cool than the stock small one. and you have no worries about leaking coolant into trans fluid (although i think that was only on a few of the older rads).