Agreed if you're getting a Mk3 leave it as it is!

More likely you're gonna get a Mk4 tho, so you just really need the arches and side skirts, wheels, colour coded spoiler and to take the black bits off around the windows and down the centre pillars.

Interior wise front recaros to match whatever pattern you got in [they only did 2 types for the mk4 escort] and you're set

Buy one already done tho, its cheaper or you might as well just get an RS turbo to start with