My Mk1 has the 'Clipper' factory installed body kit, which includes larger, body-coloured bumpers.
See also How to remove rear bumper.
You'll need
The front bumper has 2 long "arms" that protrude into the engine bay.
Unclip the wires to the indicators.
Remove the bolts from either side. One set is located near the fan belt, the other is a little harder to get and is underneath the battery. Note: the horn shares one of the same bolts. You may need to detach the horn or set it on something (like a brick) so it doesn't dangle by its wiring.
Slide the bumper out towards you feeding the indicator wires through from the engine bay. Be ready to take the weight of it. It is heavier than it appears.
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