Gt a 6 speeder out of a mk4, it will fit but you will need to change the flywheel, clutch, poss drive shafts (100mm inner cv's, I think 16v guys will be OK), gear selector mechanism as it will be a cable shift and the clutch actuation is hydraulic. You can convert the clutch to cable with parts from your friendly seat dealer, oh and the speedo is electronic so you will have to use the mechanical parts to make it work. (I am looking into the 6spd box for my mk1)
Steve.
Or fit a diesel box, that will have nice tall gears
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