I am considering changing the gearing out in the rear of my 1968 Galaxie 390/C6. I have researched it extensively and read more opinions that I can count. Of course each case/car is different. Based on all that I read I am leaning on going from the stock 270 to a 3.5. I am looking for a little more street pep without ruining my highway driving. What are everyone's thought's, impressions, comments or opinions?