cobra427mnsi,
Just guessing...
Lights: if you've got the connections to the lamp mixed up you could end up with the ground to the Low beam connector, low beam hot to the ground connector, and high beam hot to the proper high beem connector (and/or swap the high and low beam lines but keep the ground to the low beam lug).
What will happen is that the low beam will look ok, but when you switch to high beam the current will flow through both filaments in the bulb, giving not a high beam, not a low beam, perhaps brighter than low beam but not nearly as bright as a high beam. Also you'll get some current flow back through the high beam leg when the low beams are on.
Suggestion: swap the ground and low beam connection to both head lights and see if that cures the problem. If not, reconnect as before and then swap the ground and high beam. One of the two should get you 99% of the way there. The last part is if it appears that the high/low beams are backwards (after fixing the other problem) swap the high and low beam leads.
Blower motor: If the volt meter on the dash is dropping when you turn on the blower motor it would appear that the positive lead to the dash is also supplying power to the blower motor. Two possible fixes: use a relay at the blower motor, let the dash switch turn on the relay, wire a 12 awg wire from the fuse to the relay and then to the blower motor. -OR- beef up the positive wire to the dash, 12 awg or so.
Disclaimer: electrical problems are VERY tough to troubleshoot without actually putting your hands on the suspect parts ... my suggestions are simply guesses
