Like BigMike said; 35's are a lot of tire for that Dana 35.
Replace it, upgrade it or plan on carrying spares.
Think about it this way:
Put a grape on the end of a toothpick and you have no problem holding it up without it breaking. That is what the toothpick was designed for.
Now put an apple on the end of that same toothpick. It may hold for a while, but it will break. Like that toothpick, your rear axle was not designed to turn or hold the weight of that large a tire. It will eventually fail, and when it does your D35c does not retain the tire and rim. The axle shaft will slide out and you will be sliding on your spring.
The 4 banger might not be a problem, competition buggies are running smaller engines all the time, but what transmission and gears are you running?
I am running 35s. I have the 4.0L, AX-15 transmission and I am running 4.56 gears.
You would probably need to be at 4.88 or higher if you have the auto trans.
The hand throtle is usefull if you have a manual trans and have a hard time working three pedals on big rocks.
You can set it just high enough to keep you from stalling it when you are in a tight spot.