sorry to be a complete plonker but
how do you know if your disco is 1 2 or 3 im a bit confused
also what is the best diesel engine to have
i know its something simple but just cant see it

early ones were disco 1.
very latest shape ones are disco 3.
middle ones are disco 2. (98-2004).

td5 engines are very good but complicated (electronics). hence can costalot to fix.
early ones were simple and cheap. ish.
pays yer money and takes yer choice.