Conrad Schnitzlers work, as great as it is, is nothing like E2-E4. Basically, Schnitzler made proto-industrial, kind of what Throbbing Gristle tried to do (exept for all the silly "subversive" crap), only much much better. Still, his Blau-record has a nice summer-feel to it, so maybe...
Anyway, the closest you'll get to E2-E4 is probably some of Schulzes solo works, in particular Mirage (winter to Göttschings summer, though), Body Love, Inter*Face, En=Trance and Miditerranean Pads. Especially Miditerranean Pads. It's also the best record ever made.
Schulzes Richard Wahnfried-project is very uneven. Miditation and Tonwelle is closest to ordinary Schulze, and probably closest to what you're after here. Tonwelle has Göttsching on it. Time Actor has lots of weird singing/recitation by Arthur Brown. Has a charm in it's own way. Megatone, on the other hand, is an awful attempt to combine Schulzes pulsing synths with hard rock, a big mistake!
Another Schulze project maybe slightly approaching E2-E4 is the one he did with drummer Michael Shrieve, Transfer Station Blue, has some guitar playing too (by kevin Shrieve).