[84LX89GT]

Working at a dealership i see all sorts of things, one thing one don't want to do is buy bulbs that draw more amperage than stock. Ford runs as small a wire as they can get away with and if you increase the wattage of the bulbs, this increases amperage through the wires and can start melting connectors as well as the wires. So if you buy new bulbs make sure they're rated at the same Wattage, or if not, make appropriate repairs such as rewiring the light circuit (which it sounds like you really wouldn't want to do).

As for your question it's very debatable. In clear driving, blue itself is easier for the eye to see and as such when it reflect off objects at night it's easier for you to see and as a byproduct of this cops see you easier and can cite you unless the bulbs say 50 state legal on them.
A drawback to the blue/white bulbs is that stock halogen yellowish bulbs cut through fog better and less of it reflects back to you, this goes with snow as well. The stock bulbs are more of an "all-weather bulb".

When you replace the bulbs you don't have to have the housing re-aligned. the bulb is just in the back of the housing and there is a retainer that you turn counter-clockwise (counter-clockwise looking as if you were inside the engine compartment looking forward) in the back of the housing. All you have to do is loosen the retainer until it pops off and then pull on the connector to pull out the bulb and connector. Then you just pull off the connector from the bulb. Note before you remove the bulb or as you moving it out how the connector tab faces because there is 3 uneven spaced notches that the bulb slides into and getting the bulb back in can be a pain if you don't remember how it came out, normally though the connector tab on the bulb faces upward.
Good luck,