I pulled a 17 ft. Triton for several years with a V-6 Chevy S-10. Before that I pulled a 16 ft. Tracker with a Merc Sable. The problem you're going to have is backing out into the water far enough to float your boat without getting your exhaust pipe under water. If FWD means front wheel drive, you probably need to carry a bag of sand with you. If the Cypress Cove ramp is the ramp on Rebecca Creek, you don't want to go anywhere near it.
If you're going to venture out on Canyon in a 12 ft. jon boat, you might want to make sure your life insurance is in order. You might be safe back in Tom Creek.
yeah rebecca creek ramp LOL. but feel free to use it, ill pm you my number and ill come pull you out when your done fishing haha.
Does your trailer have a wheel on the stand? if so you could put a little pressure on it making weight go to your front tires.
As far as safety on canyon lake, just dont go when there is alot of traffic on the lake, they all ski and drive careless.
you might look into getting some stiffer springs for the rear of the car, it would help out alot.
Also even if the exhaust goes in the water, dont shut the car off and it will be fine.