IF you use the 60/55w H4 bulbs, then the existing wiring will work just fine. However, using the O.E. wiring to connect the 100/55w bulbs is risky from what I've gathered on this board.
Would be wise to re-wire with higher gauge wiring if going with the 100/55w's.
Good luck and enjoy your much improved lighting!
'91 300E, 212K miles