Fender to tire clearance on tandem axle trailer?

We have a 16' plus dovetail tandem axle open car trailer that we bought used. It needs some new fenders, so we bought some and are ready to mount them. The old fenders were mounted pretty high. We would like to be able to open the door of the car over the fenders. My question is how much clearance do we need between the top of the tire and the fender? The trailer has dexter axles with leaf springs. The top of the axle to the bottom of the frame is about 1 1/2" so in my mind the tires shouldn't have any more upward travel than that or the axle will hit the frame of the trailer. Can anyone offer some assistance?

Sounds like you answered you're own question. I would give it about 2". You could also make the left fender removable. I had a trailer like that.

On an open deck trailer removable fenders rock!