Dads like rc too

You can go crazy with the aluminum parts. It adds weight and it bends. The plastic steering knuckles are prone to strip out though. When you replace them with the alloy ones, you can loctite them in, the plastic ones will not. The plastic replacements are very inexpensive. Some people just choose to replace them with the plastic ones. If it becomes a problem for you, at least you'll have some info to help you decide. The gas tank is just a matter of fitting it. I don't think any of the larger tanks will just bolt in. Just get creative. People have relocated the tanks to wherever they find it easier to fit. As far as the servos go, check Nitrosports threads, he recommends a good inexpensive servo all the time that wont break the bank.