On my sids shifter I would like to remove the rear cover to do a slight modification.

1. Is it a straight remove and replace job?

2. Do I have to worry about gasket thickness like other gaskets in the transmission?

3. It is magnesium correct?

On my sids shifter I would like to remove the rear cover to do a slight modification.

1. Is it a straight remove and replace job? yes. you do have to keep the gear that sits inside the rear cover in place when you lift off the cover. If it falls on the floor, just make sure to put it back before you close up the case.

2. Do I have to worry about gasket thickness like other gaskets in the transmission? no

3. It is magnesium correct? yes

thanks!

One tip, that I have not tired, is a bit of grease to hold the gears in place when reassembling. It can be a bit fiddly otherwise.

Get other confirmation before doing that in case I am wrong.

As @mepstein said, get ready to catch what will want to fall out.