I made this quick attempt a few days ago following Wingsley
(It was easier to re-build the upper section from scratch and since this was just a test of the forward section I didn't add the hanger door details at the rear.)
Hmmm, I think I prefer the look of the thinner "dome" above the sphere section from the previous models, so I'm going to stick with that.
Also, I've started the model again, this time taking more care with the shapes and proportions. I've no images yet, but I should have something soon.