There are more differences between the two.
This is for the 1/48 Monogram kit, right?
OK, your kit shows an -E in every basic respect, except for the nose landing gear. On the -E, the nose gear should look like this:
The nose gear in the Monogram kit, if I recall right, represents the later style that was found on the -J model, like this:
http://data3.primeportal.net/hangar/howard_mason/f-8j_150297_painted_as_f-8e/images/f-8j_150297_painted_as_f-8e_41_of_52.jpg
Notice the two small "horns" at the front edge. Also, there is another part that may be incorrect in the Monogram kit. Look at this link:
http://data3.primeportal.net/hangar/howard_mason/f-8j_150297_painted_as_f-8e/images/f-8j_150297_painted_as_f-8e_44_of_52.jpg
Notice the large part, the one that's shaped like a V? This is the -J landing gear, and the part is I believe a part of the retraction mechanism for the nose gear. On the -E, this part has four lightening holes on the starboard(right) side and three on the port side.
There are other minor differences, ones that most people would never pick up on in this scale, such as the ailerons being different. The -J's had a blown BLC system, so there were vents in the top of the hinge line on the ailerons that were visible whenever the flaps were down. Which reminds me, if youre going to build this with the wing raised up, be sure to drop the flaps because they would drop automatically whenever the wing was raised.
It all depends on how much detail you want to be correct. The -E and -J used two different ejection seats, for example. Most people, again, would never know the difference. One other thing I do want to mention is that the Monogram kit's main landing gear is incorrect for the plane. There is an aftermarket set of landing gear that fixes it to the correct height.