if its leaking at front of box could well be a front bearing going hence the judder

its ok mate ,yes right kit and drums are the same

yes but that has nothing to do with altering t/box ratio, with the 1.2 box fitted in a defender you have the same ratios as disco but usually taller tyres,its the tyre were over gearing is going to occur

1.2 lt230 fitted to 300 tdi disco is the same as fitted to defender r380s are the same except the gear change,diff are the same only variant is tyre size,later q boxes are equivalent on both they just have finer teeth than tdi boxes

yes

243744 x 2 243743 x 2 576973 drums rtc3417 shoe set

for what

yes 109 should have twin cylinders thats what gives the increased front effort,88 only after 1980

no r380 and the lt230 are same as fitted in manual disco so are the diffs so its only tyre size that might vary,defenders tend to run taller tyres so it ups the gearing as such

the only difference between the disco and defender would be the tyre size

compare them if they are all the same length they are ok

cobalt drill bits,those threads are 14 unf iirc which is odd as it was usually coarse ie unc in castings

thats the adjuster the cast iron one is series 1 early series 2,there is only the 2 types

grind it flat center punch it and drill it out with smaller drill than thread tap size

no, shaft goes right through the box and has 2 gears secured with a difficult to get at circlip

3 bearing crank, blocks are duck egg blue unlike 5 brg which are red lead colour

2.25 3 brg

the pin wont drop down until the shaft below it hole lines up which happens when the red lever is pulled back and outer shaft behind the tin cover slides forward

its abs axle possibly defender td5 but all the later defender disco rrc axles are the same except the brakes and mud shields

have you a pic of the brakes,measure radius arm bracket width as well