That is a bit of a hybrid. Mk1s don't have louvres in the front wings as they only came in with the Mk2. The sidelights and the larger wing finishers are correct for a Mk1. Nice colour BTW.
The bumper has been altered (rather well I must say) to remove the centre section. Some that I have seen have been just cut, this one has been nicely shaped to mimic the outer ends. It doesn't achieve anything on a Mk1, other than an altered aesthetic.
My RBRR co-driver is keen for me to do this on my Mk2, particularly after I let on that had a spare front bumper. I think it could look nice if done properly and would increase airflow into the radiator.
In order to put a Mk1 bumper on a Mk2 car, I think you would need Mk1 hinge boxes (which are welded to the chassis) and bonnet tubes. Mk2s have one piece side/indicator lights which should still be OK with a low bumper.
Ian