20b assembly and disassembly?
 

So I want to do a 20b build and I need some help. Where can I find the info I need for assembly and disassembly of the engine? Like torque specs and how to take the e shaft apart and put it back together.

Use 13brew specs and its basically a 13b with another rotor stuck to the front,
some of the shafts aren't too bad and you can man-handle apart others can be a bit tight and you might need a pulled to get apart, there is a threaded portion in one of the lobes of the e-shaft to help facilitate this.

So dose it just slide in and out no tools required or how does that work exactly?

remove the front stack keyways, front plate, housing and rotor. then like I said you may need a puller to separate the two halves as they can sometimes be a bit tight, mine wasn't.

So it's just pressed on? What how do I put it back on for reassembly?

im pretty happy i got mine apart last night.
i was banging on the front 32mm eshaft nut for about 6 hours with a crow bar wedged between the front lobe and thick iron. i think my problem was using a 4lb soft hammer didn't exert enough shock into the assembly. so i used a 2lb tiny solid hammer and carefully, squarely hit the front nut about 10 times trying not to miss a strike and hammer the thick iron face, i spoke to atkins rotary and he told me that as you hit the e-shaft it is only pushing against the gears and should not ever do any damage, so you can confidently give it a solid whack. just have the engine laying horizontal and put some force into the crow bar and wrap it in something to cushion the bar from scoring the iron or eshaft. these pics helped me alot

notice the nut threadded into the front of e-shaft?
that's so you dont have to damage the shaft with your hammer, and gives a good sized surface to aim at. i was trying for hours but when it came loose i really didn't expect it to.

So the front lobe just slides on then.

Pretty much

It is a taper fit, just like the rear counterweight/flywheel. No big deal.