92 crown victoria questions

I've recently bought a 92 crown vic. The car is by far one of the best rides that i've had, i just has a question about the fuel filter. Do you guys think that it would be ok to just disattach the line to the filter, and let it run in a bucket instead of relieving the pressure properly? Apperantly walmart use to do this, when they use to repalce fuel filters... Do you guys also think that i should use the NOS fuel injection cleaners? Also would you think that the Mass air flow sensor could result in bad fuel economy. I'm getting somewhere along the lines of 13mpg. i have a rusted exhaust pipe, and some guy told me that crown victorias are specially sensitive to that. I think i will try and get the spark plugs also replaced.
Any suggestions are much appreciated it.