d21 engine and gearbox swap

[redness1]

Greetings from Australia
I have an 86 d21 Navara dual cab 5 speed z24 but its full of rust and the paint is really bad.
I have found another 86 model the same as mine but in a lot better condition just down the road but it has a blown head gasket (or head) and its floor shift auto.
My question is how hard is it to swap a z24 and do a manual conversion at the same time and is there any tips and tricks involved as I've never done a swap before.
Also can I pull the motor and gearbox out as one or do I need to seperate them and what is involved in putting the manual brake and clutch pedals into the auto body.
Are the diffs the same ratio between auto and manual and will I need to cut the floorpan to fit the manual shifter.

Thanks in advance guys and girls