I am sure this is going to turn out being one of the best mods this car needs
I have a DIY Mishimoto MMRAD-T200-94 Celica GT radiator installed and decided to use the stock fan as well, no shroud but mounted to the standoffs on the radiator, Setrab oil cooler, DHM big IC and bumper, opened up grill. The radiator install was a huge task and not one I would do again if I could buy a direct fit Mishimoto!
I have not tracked the car but some pretty spirited driving on a hot day up a canyon road and making 300WHP with no heating issues at all. Not fast but quick runs and used boost to pass quite a few cars, quickly, around 600lbs in the car with myself, my wife, two big dogs, cargo, up over the I80 from Reno to Sacramento, again hot day, no heating issues and I have not even finished sealing up the air flow to the coolers yet.
If I am having this much success with what I have done I am sure the direct fit one will be even better
You are going to make a lot of people happy when this is finally done, glad you are taking the time to do it right!
Rick