another 360/408 over heating

Would like to thank everyone for your thoughts. Here's what I can tell you to answer your questions or tell you additional things I may not have put in other posts. First this is in a 66 Dart. Originally was a 273. All pulleys are from the original motor. My water pump snout to radiator clearance is only 2.5 inches at most. So a fan clutch will not fit unless there's one I haven't looked at yet?? The shortest one I found was 2 5/8". I can put the original 4 blade fan on and give that a try. I pulled it out a few nights ago and was thinking of trying it. Is there a steel 6 or 7 blade that would fit with my tight clearance? I would have no shroud to fit it so I would need to fab one up.
As for the holes that I put in the shroud, again I just did that and the reason was to see if that helps cool it while driving as the temp does climb while driving (up to 220*+) and I want to see if air flow from driving would at least cool while moving. As for how much air the electric fans pull I would tell you it's a surprising amount. Problem is they are only 9" fans because I had to stagger them around the water pump due to lack of space. I originally had bought a large single electric fan with shroud but it would not fit between the radiator and water pump snout.
As for the playing card I did not try that but I will. I did put a shop towel (the paper type) to the outside of the radiator and the fans pulled that tight against it.
Lastly, as I said in the original post my timing is at 14* initial and 34* at 3k. Plugs look good so I'm not thinking a lean condition at this point.
I'm away for the weekend so I probably won't get back on this until early next week but if you think of anything else please post. I'm open to trying anything that would help!
Thanks, Rod