HAHA you guys all suck. They make seats that contour to our buckets. My wife does at home daycare and we have 5 car seats in our Expedition and whenever she orders another I find the bucket style so I can fit them in my cars. I know this one fits for sure
http://store.summitracing.com/defaul...=egnsearch.asp
Thats expensive but I bought it to be cool. Heres a regular Graco that will work also. Notice how the bottom is not flat but instead somewhat curved
http://cgi.ebay.com/Graco-Ultra-CarG...QQcmdZViewItem
NOTE: I am imbarassed to admit, but one day I was watching a saftey channel and they were installing a carseat so I was intrigued. Once installed the lady pulled the seatbelt all the way out and when it began to retract it clicked. I never pull the belt all the way out and didn't realize it actually locks as it retracts back in. Once it is retracted I put all my weight with one arm into the middle of the car seat and push down, with the other tugging on the belt to make it tight. I have never made a seat so firm before I learned this. My first child would side around sometimes in our family car if it was not tight enough. I hope this helps you.