Normally the WP housing does not seem to matter too much as long as it bolts up and the WP clearance is close. I don't "think" shrouding of the original 22" opening and 26" radiator is a big issue either.

The condition of the radiator matters, shroud and good fan matters and drive ratio/WP type matters. An original spec 3 or 4 core radiator can be good as can a 2"+ thick aluminum radiator.

Is it hot while rolling down the road? Hot a idle/slow speed? or both? Hot rolling usually means the radiator is not effective or water flow/water pump is not enough. Hot only at idle/low speed usually means fan/airflow is not adequate.