47 Knuckle Gas Tanks

[Gomer]

First post so take it easy on me.

I'm looking for original tanks for my 47 knucklehead and have a question.

I know the right tank fitting on 47 tanks are 2 1/4" from the bracket and Panhead tanks are 3 1/4" so that is easy to tell.

But what do the bottoms look like? Panhead tanks are suppose to have more relief in the bottoms to clear the heads right?

Hear are three pictures of tanks from Ebay and I am expecting more difference in these bottoms. Before I shell out $900 I want to be sure what I am looking for and any help would be appreciated.

Blue-47, black-48, grey-46or earlier

Thanks in advance.

[Chris Haynes]

Here you can see the difference between the Knuck tank on top VS the Pan tank below.
Thanks to Bruce Palmer for supplying the photo.

[Gomer]

Thanks Chris
Great view of the difference, not evident from the views I had.
How about the right tank? same as panhead except for fitting placement?

[Chris Haynes]

Thanks Chris
Great view of the difference, not evident from the views I had.
How about the right tank? same as panhead except for fitting placement?

Both sides of the Pan have clearance dents. But the right side is easy to spot by the fitting.