Looks like a small left hand tank. Seeing as how there's a single bolt (per side) subframe in the photo and he has a 1989 rod change gearbox also for sale, I'd bet it's got a bayonet style sending unit.

It looks like an early one by the pics posted in the classifieds section but no picture of the sender.

Having no contact info in your profile and not much info about which tank you have will limit interest. My e mail is in my profile if you'd like to contact me and we can see where you are located and what you have to offer. I have several customers needing a correct tank. 

I'll be taking a look inside a large left hand tank later today. It was the worst looking tank I have done. I started by pumping all fuel out, then turned upside down and poured a couple of lbs of wet rust chunks out enough to fill a 1 qt. freezer bag when dry. I have a out side sill cock which is plumbed to a valve that allows hot or cold water to the water hose. After flushing with the water hose and Dawn dish I put the exhaust side of the vacuum in and ran it till dry. Once dry I sealed the tank and put 5 gallons of molasses in and started turning the tank daily. After a week I poured the contents out and again flushed with hot soapy water and used a Moroso bore cleaning brush to break up any patches of rust viewed though the holes in tank ( fill and sender opening ) till fresh water came out. While so much better than starting point I decided to seal the tank again and fill with 1 gallon of rust solvo and a lb. of flat washers of different sizes and a lb. of rock polishing media. We then placed the tank in a tumbler for a week turning 90 degrees every other day. I was running late yesterday and picked up the tank and poured the contents out ( very rusty looking liquid and the bits ) flushing again with hot soapy water till it ran clear. My flash light was burned out so I put a gallon of diesel fuel in sealed up and tumbled again over night. I hope when I open it up today it will be as clear inside as new. Steve (CTR)

Assuming the Left Hand Drive car was a saloon, there were two sizes of left hand tanks, as well as different ones for the larger size depending upon for a carb car or a fuel injected car. There were also two different smaller ones depending upon how the fuel sending unit fitted. Which is yours? Maybe post a photo or two.

I have a gas tank that is in great condition, for sale. Please let me know if interested!