instructions for the dismantling of the Bachmann HO scale Climax

[Fred A]

Would someone point me in the direction of obtaining instructions for the dismantling of the HO scale Climax gearbox.

I recently received some collars from a friend on Vancouver Island and these were pressed onto the split bosses on the drive line, these worked and fixed the slipping problem, but now, there seems to be slipping inside the transmission, I have removed the bottom cover and can tell you all, the final and intermediate gear are OK, from there, I cannot see any further into the transmission, I might add, the crankshaft and rods are working OK.

I also notice the Bachmann is offering gears for the shays and climax on this page

[ABC]

Here's a link for a PDF for the exploded parts diagram: http://www.bachmanntrains.com/home-usa/dwg/dwgs/H828X-IS001.PDF

[Fred A]

I have this PDF, I want the detailed instructions for the correct order of dismantling the transmission, and I guess this will be a big ask.