Ford Truck Enthusiasts Forums - Aftermarket 6.0 Cooler and Radiator ?

So my re gearing will have to wait. I was installing my trans temp gauge and was treated with a nice “ Strawberry Milkshake “ colored transmission fluid.

Here are my questions. The truck is the one in my signature and its primarily used for pulling a boat and camping.

I will be upgrading to a 6.0 cooler but the one from ford is 350-400. I can get an aftermarket manufacture 31 row on RockAuto.com for 205+shipping. Is the one from ford really worth the extra 150 – 200 ?
Will a aftermarket radiator work just as well as the one from ford ? Mine is a 1 row right now will want to convert to a 2 row I think they were stock on the V10
Several trans shops said because I am going to be doing a 100% rebuild there are some things that they all said I needed to do

Converting to a 6 pinion forward planet gear set ( is there a way to tell who actually makes these ? Motorcraft or aftermarket mfg ? )
Converting to a 4 pinion overdrive planet gear set (is there a way to tell who actually makes these ? Motorcraft or aftermarket mfg ? )
Transgo HD2 trugger
Staying with the Borg Warner Clutch's
Mag-Hytec trans pan

Here is where I get confused on the fluid. I have had several recommendations for the following

1. Transynd ( used in Allison transmission fully synthetic trans fluid )
2. Amsoil Torque Drive ( on there website has a compression vs. Transynd and Transynd is a little better )
3. Motorcraft mercon IV

I am leaning towards the after market radiator and trans cooler and Transynd but wanted to throw it out there to see if anyone else has any feedback.