not very mate, just some 1.5mm or 2mm thick steel vut/bent to a rough shape, then welded in.

the guy that fabbed the cage for me would probably be willing to fit it into yours, but i dont have a clue on costs - i can ask tho!

it was made by caged in frome, so again, not a million miles from you.

or even x-sport in basingstoke could do the fitting