Classic/Antique Car Repair: 47 Chrysler Fuel Sender Unit Mounting Problem?, machine screws, gas tank

Question
Hi Dick, I recently purchased an aftermakrket gas tank from Tanks.Inc for my 47 Chrysler. It is a decent tank, complete with vent/rollover valve, baffles, and the sender unit hole lined up quite well with the access cover in the trunk of the car. I did have to do some minor modification for the hanging brackets for a good solid mount.
Here is my question/problem, the sender unit hole has the typical 5 tapped holes for the stock or aftermarket sender unit to mount to. The sender does go into the hole and will mount in, the problem is this, the 5 tapped holes for the machine screws were placed in such a way that the stock sender float arm is going in the wrong direction to the rear of the gas tank, instead of toward the front. Because of this, the float arm and float hit the back of the tank, because there is not enough clearance.
What might be a remedy for this, could I drill new holes in the sender unit to change it's mount position, should I drill and tap new holes in the gas tank, or could I make an adaptor plate to go between the sender unit and gas tank.
I know this is a bit of a modification question, but I need help with this one, and am not sure how to proceed.
I would have stuck with a stock gas tank, but the 2 I have were beyond repair, and I could not find another, so I went with a new aftermarket tank designed for 1941 to 1948 Mopars. Thank you in advance if you can offer any suggestions/ideas......Fred

Answer
This seems very odd to me - I would think the folks who designed the tank would have known to avoid this situation - I would guess there is an error in the "clocking" of the hole pattern for the sender.  Every tank that I am aware of has the  float arm pointed back in the tank, not toward the front wall.  

According to the parts book, tank number 1120875 is the same for all 6 cylinder MOPARs.

If your car is not a 6 cylinder, then you have a more difficult problem.  If the supplier cannot furnish the right tank for your car, perhaps you can talk him into making one with the sender angled correctly, if that is the only difficulty.

If you cannot get the right tank from the supplier, I guess my choice would be the adapter plate, because you can make it such that there is a good sealing surface between the tank top and adapter, perhaps with a groove to accept a large "O" ring for a seal.

If the tank they sent you was supposed to fit your car, there was probably a mistake made when the mounting holes were made.

Dick