I have a 454 in an 85 El Camino and I'm installing the rad with an Olds fan shroud and metal top plate. Issue is my 19 inch fan blade hits the shroud at the top front where the shroud is angled. It doesn't hit by much. My first thought was to modify the fan blades for clearance. After some research to try and determine orientation of the fan because of curved tips, I thought of going to an 18" fan. The larger fan fills the shroud opening better than the 18" fan would, but don't know if I'll lose airflow with the smaller fan. Anyone deal with this issue? I'm not interested in running electric fans and I'm sure that suggestion would come up.