I had some new BMW R100RT exhaust pipes rechromed before fitting (the plating on new replacement BMW pipes burned off in under 500 miles & I had the warranty replacements rechromed in the UK before fitting) and they had been chromed over the ends. They took a lot of work with a Dremel to grind off the bulges to get the pipes to fit both into the heads and to allow the silencers to slip over the pipe. Chrome plating is very hard !
In this case the new plating looked very good & didn't burn off, but the plating thickness caused other problems - small blisters came up in several places, presumably due to the thicker plating expanding due to the heat (BMW airhead pipes are single skinned). Still looked better than the BMW original plating, with dull patches where the plating just disappeared.
Best option to let the supplier sort the problem by supplying parts that fit - I'm sure Phil will sort things out for you when he gets back.