I have been reading this thread and wish to clarify...
The DHP consisted of lowered suspension, larger 17" wheels, Pirelli P Zero 245/50 x 17 low profile tyres and a front grille painted in the same colour as the body.
The engine and transmission were standard.
The DHP was never available on a Mark 3.
The DHP was introduced with the 1997 Mark 4 cars.
I have owned mine since new in 2000 and it was ordered especially with this pack because I liked the wheel design. The car replaced a Mark 3 which, in turn, had replaced a Mark 2.
And that's about it, really.