I owen a 99 with an auto and have made a few upgrades. 4" exhaust, K&N and a banks intake. I plan on installing 300 Hp. injectors and maybe a banks big hoss chip. I trying to stay in the 350 hp. range. My question is would it be better to upgrade my current trans or go with an aftermarket. If an aftermarket which is the best. I do little towing mainly a 16' flat bed with a racecar on it and a 27' fifth wheel camper. thanks for any info.