I can tell you this about line pressure. In the 2004r with the parts that are available I have not found a downside to line pressure in the 300 range. I set all my trannys up to operate in this range. I have seen the rotor break from pressure in the 4L60 and 700. So to be on the safe side I had 20 4340 billet rotors made to be sure there are no problems and will install them in all my performance builds. 250 psi is plenty of line for most apps and with a properly set up 3rd gear circuit should have a good 2-3 shift firmness.