235's is fine with the spindles. Will probably be your best bet with your MPG concerns. If you go the full lift I would do 30's. I have 30's and my gas mileage didn't suffer. Yes your speedometer will be off some, but to regear I wouldn't bother. Just make a mental note of how fast your really going when you speedometer reads a certain number example: speedometer reads 65 -> actually means im going 70.