[sunman]

The 86-93 E7TE heads have a T cast under the valve covers.
GT40 have 3 vertical bars on end of head and GT40P have 4 bars.
The 1986 E6SE head is what I have a photo of, they were so bad with the raised valves and no valve relief pistons the E7TE truck heads were used instead and the E6SE abandoned.
Considering your build date I think you have E7TE heads with the casting number in same place as previous photo.