That E15 stamping on the engine is strange

Where exactly is it on the engine? Is it on the block or on the head?
If my knowledge of the E engine serves me correctly, the E15 and E16 both shared the same block with the differences being in the heads, crankshaft, pistons and connecting rods. I know that some E15ET people were using E16 internal parts (crankshaft and maybe conrods, can't quite remember) to increase the displacement for more power. The E15 turbo head is said to flow better than the E16 head.
The transmissions for the E15 and E16 engines are also different, or at least are different for the E15 turbo engines. The E16 transmission has the starter mounted to the bell housing at the top. The E15 has the starter mounted to the bell housing at the bottom. I remember E15 turbo people saying that an E16 transmission can be bolted to an E15ET but it doesn't last long unless you're gentle.
I don't have my E engine anymore, it went with my old Pulsar when I sold it. I just moved to a new city 3 weeks ago so my desktop computer with all my pictures of my Pulsar and the E engine is packed away
I miss that car... I'd still be driving it if it hadn't become structurally unsound because of rust. I sold it to someone who owns an N12 so its spirit will live on through its parts

. Mine was actually the generation before yours with the E16s carbed engine. The only swap I did was a 5 speed swap from an '88 E16i equipped Pulsar NX when the 3-speed auto died.
Another interesting thing about your car... it looks like you have the front bumper off the SE model (CA engined). Yours is the XE model since it has the E engine in it.
This is what the XE bumper looks like, it's a bit different than yours:
*EDIT*
Wow... I wrote that much on the N chassis and I could have written even more. er... does that make me a Pulsar nerd?
btw, if you have any questions about your car, feel free to ask.