Brakes

it may be a somewhat stupid question, but are 90, defender,Range Rover classic & discovery 1 brakes all the same calliper?

No. Disco 1 for a start can be twin circuit or single circuit for a start... and some are different thicknesses for vented discs... I think they all have the same bracket holes but I stand to be corrected - you can for example fit single circuit Defender calipers for thick vented discs on a none ABS Disco, if you ordered the same for a Disco you would have twin circuit ones only because it would assume you are ABS fitted....

Discovery 1 bolt holes are smaller than defender 300 - don't ask how I know

Let me guess - ones an M13 and the other is a 3/8th thread...?

Not sure, but I had to drill out the holes in the caliper to fit the axle I had.

Ah I get you.

How annoying!