Ok, seems like consensus to wait with injectors provided I go convervative when tuning.
My neighbour is really into cars, so I can borrow his lift when I want to, as long as I complete the task in a week or two.
I like getting my hands dirty wrenching my cars, so labour is "free". I'll try these downpipes and see how they hold up.
Next step would be injectors, pumps and ethanol. But I'm not sure I'll ever get the urge for E in this car.