Per Haynes, the torque for those screws is 8 - 10 ft lbs ... I'd stay on the low end of that range. 10 NW is the usual value for that size screw .. that works out to "7 point something" ft lbs.
I believe the idea behind reducing the diameters thru coolers is to speed up the fluid velocity ... hopefully keeping particles suspended so they won't fall out in the cooler coils.
I can't help you just now on the part number for the filter ... but be sure you're ready for the difficult filter seal. I keep reusing the one that is stuck in the tranny body.