I've never used a hat on my HEI's. I just screw the coil down on top, push the plug wires in place, and go on with life.
The coil wires have male terminals that fit in the cap where you plug in the harness. I don't have a "harness" (per se), so I just plug a hot wire on the hot terminal and the tach wire on the tach terminal. Works mint.
I could give more detailed info if it weren't still dark out. It's one of those things that I have to be looking at to tell you "exactly".
The post below entitled HEI Wiring
gives good details on the wiring, in case my description is confusing.