New fuel tank in, but gauge backwards?

[jeepardy]

A friend had me install a new fuel tank on his 1977 CJ7 . When working on the wiring, I noticed his fuel gauge is backwards. Empty on right, full on left. It seems to work as you can see in the pic, put 5 gallons in and went to over 1/2 full. Had some in it before.
I checked my 76 CJ5 , 83 CJ7 and an extra gauge I had from an 86 CJ7 and all of them had E-left F-right. Haven't pulled gauge to find part number, and don't know if its after market.
Anyone see this before, is this gauge from a DJ or RHD jeep?

 

[CJ]

I agree, looks like it is for a RHD. But this RHD CJ has a fuel gauge that is oriented as I have always seen. -->> http://www.jeep-cj.com/forums/f49/83-right-hand-drive-cj-3023/index2.html#post25846