Bare chassis photos required

[dmc4087]

Its probably your oil sender unit leaking on the drivers side, and not the sump gasket.

[stunned_monkey]

dmc4087 Wrote:Would a bad connection to the gauge or light still cause lights etc to be dim?

No.... use the miltumeter to probe across the alternator to see if it's struggling to maintain votlage or if the drop is elsewhere. I'd probably lean towards the alternator being on the way out actually.

[stunned_monkey]

dmc4087 Wrote:Its probably your oil sender unit leaking on the drivers side, and not the sump gasket.

Not if it's leaking at the flywheel end - that's more likely the rear main.

I totally agree that it's almost certainly not the sump. And the bolts are easy enough to get to - you just slacken off the engine mounting studs and jack up the enging a couple of inches. An 11mm ratchet spanner is extremely useful here!