If you are referencing oilcanhenry's post, he is talking about an actual oil line from the engine to a mechanical gauge under the dash, I've seen them also, and never seen one NOT develop a leak.

 

rear main seal has nothing to do with the oil pressure sending unit screen

 

that is how mechanical oil gauges work. the unit is in the gauge not a remote sender like an electrical oil pressure gauge. the plastic tube with oil runs into the back of the gauge in the vehicle.
mechaical gauges time has past. trying to run a plastic hose into a crowed modern vehicle is a pita. it will be hard to route the tube as it can't bend tight t urns.

 

Yes, the days of the hot oil running inside a cab to a mechanical gauge are done with. I adapt to what I am driving and use that the best I can. That oil screen sounds like it has never been changed with all the shots taken at the dealership tech for not doing it at the same time as the rear main seal assembly. https://www.rockauto.com/en/moreinfo...433403&jsn=984

The screen is up above and kind of a PITA to get to but should be changed. Or you can go OLD SCHOOL and just leave it out.

By the way, why haven't you found a trustworthy shop with qualified techs that can do the work on your rig instead of the "stealership" you go to. No arm twisting being done to get you to the dealership.

 

I have installed oil pressure gages ( mech) on several vehicles since mid 70's Not one of them ever leaked ! if they leaked then installer must of messed up ! and yes it had a line for oil , mech gages dont work to well with out it

 

It was long ago, but yeah you can bypass the sensor that lit up the low oil pressure light on the dash (at least you could back then) and have the engine oil going to a gauge under the dash, not to the electrical sender on the dash readout since there wasn't one, unless it was an option. Lots of cars only had a light that would come on if the oil pressure was too low, and not just Chevrolet. For that matter, even air-conditioning was an option, and not standard as it is nowadays..

I just looked at one that had only an oil pressure light, but it did have a stock tachometer. Likely why my friend added the direct oil pressure gauge, instead of just a warning light. Most ordinary cars back then had no tachometer at all, unlike most cars today do. Most cars (not just GM/Chevrolet) just had a light for the battery voltage level as well. Different times.then nowadays, to be sure.

Ever heard of a "three on the tree" transmission shifting lever on the column? Haven't seen one of those in many years, but a Chevy Chevelle muscle car would never come with one of those pieces of junk. They were only on very cheap cars or pickups.

 

My 1966 Chevelle SS had a three on the tree and a 283 . originally , then I swapped it for a 396 that I built and a 4 speed ( I just installed 4 speed, not a transmission dude)