PackardDon wrote:
Yes, I had my 1940 110’s shortened when I added overdrive but that was decades before the Internet where finding the proper one is much easier. The compromise rear end (my own terminology) had a ratio that gave adequate power from a stop while lowering the higher speed rpms but the proper one for overdrive will be far zippier from a stop and the overdrive will handle the high end by reducing the rpms by about 30% when engaged.

As ring and pinion change is doable but likely more work than changing the unit.

PackardDon wrote:
They are 550 miles away at me Oregon shop and we are on lockdown here in the Bay Area of California but I plan on going up as soon as I'm able.

As for your Belair, I can't speak for that but the neighbor where I used to live had an identical one in his 1952 Cadillac. They were made, I believe, by AC but I have also seen them with the Carter logo.

PackardDon wrote:
I only ever had an electric pump in one Packard and only because it came with it (a 1953 Clipper Deluxe) and it was easier to leave it in. Some pumps have adjustable pressure so shut off when not needed while others just keep pumping. Mine was the diaphragm type which will still pass fuel through from the mechanical pump even when shut off but other types need to run all the time or they'll block the flow.

Bottom line is I can see no reason to install an electric pump and they may just be patches to cover another problem that needs addressing first. If the mechanical pump is in good condition, its valves should minimize fuel running back to the tank when sitting for periods of time.

I would, however, use a filter at all times and prefer the factory type if for nothing other than appearance. The modern in-line filters look odd to me in an old car.