What year is my engine

[KeithB53]

I own a 1987 Chevy 1/2 ton 2x2 pickup It has 5.7 L throttlebody F I
and 4 spd auto trans. I have been told it is a newer engine. It has the center bolt hold down valve covers and a small distributor, not the big HEI. But the distributor is an electronic and not the old units like for pre hei trucks. I just bought a new dist cap and rotor and I had to get ones for a 1992 to fit. so what years could it be?
thanks in advance

 

[tech1]

There should be a number located on the rear of the motor behind the distributor on the flange right before where the bellhousing bolts to the motor. It will be cast in the block raised 6 or 7 didget number. Call me at 1-800-741-1678 ex 500 and I will tell you what year motor you have.