overheating during tune up

[BarrMark262@aol.com]

Hi List: Well, now that the distributor is in right and the engine starts and 
idles, I notice that within 3-4 minutes my temp gauge goes to hot.
I have water in the radiator; the top of the radiator gets hot so I guess the 
water pump is working. radiator is recored, and water pump rebuilt. Fan is 
not loose.
Where to look for cause?

Thank you so much,
Dennis

1974B almost done