There is always the thrill of trying to fill a Lotus Elan differential with fluid after it is installed ... Anyone else have an easier way?

Method One:

I cut an access hole with a hole saw in the fiber glass bulkhead to the rear of the differential. If the hole was cut to the right size a Propshaft Access Grommet (p/n 026 B 0371) could be used.  The filler plug in the differential should be filed to fit an 11/16" socket.  It would make a very clean installation. - Michael Robertson

Method Two:

I had quite a bit of experience with this until I had the rear end rebuilt, fixing the leaky seal.

My technique involves the use of a pump designed for filling outboard motor gear cases. It is fairly compact, has a flexible hose and mine screws in to a wide mouth oil bottle.

With the pump available raise the car into a level position. For me this involves jacking and block the front of the car then pivoting the rear of the car to a level position, using one of those clever U shaped devices that lets you jack on the frame. After that, securely block the rear of the car, you will be spending a bit of time way under the car. The car should be fairly level. I always give it a test shake, believing it is better to lose a car than me and the car.

1. Use an adjustable wrench to remove the fill plug, it has a square drive.
2. Stick the hose in the hole and pump until the oil comes running out all over you and the car.
3. Clean up the spilled oil.
4. Assembly is the reverse of disassembly. - Dean Giacopassi