Jelco sa 750e

So 1.25 inch = 31.7 mm

Basically you could expand your mounting hole towards the platter by only 0.39 inch to mount another tonearm with 230mm (9.05 inch) Pivot to Spindle distance like Fidelity-Research FR-64fx. The top plate of the FR tonearm base will cover 53mm (2.08 inch) diameter above your plinth anyway.

Look at FR-64fx in my system (in the middle of the picture gallery).

Jelco is drilled thru with no arm board.

spindle to pivot is 240mm

does anyone know a better tone arm that would have that 240mm so I could mount it in the same location?

Same PS distance does not mean the same diameter of the mounting hole in your plinth. It can be wider or smaller than your current hole.

If you can modify the mounting hole a bit, you could use Fidelity-Reseach FR-64fx tonearms with 230mm PS distance and 30mm mounting hole diameter. Superb tonearm!

FR 64s and long 66s are heavy mass toneams made of stainless steel.

64fx and long 66fx are NOT heavy mass tonearms, they are made of aluminum and copper. 64fx with optional counterweight (W250) can handle superheavy carts like SPU and FR-7fz, but with stock small counterwight the 64fx is perfect for nearly all MM and MC cartridges (old or new). Those two tonearms are predecessors of the IKEDA tonearms available today (same PS distance BTW). You can read about IKEDA here.

heat lamp warms up the grease I guess?

  If there is a problem (*typically with 64s) you can try this method, but I think you’d better open/clean to add the new grease, it’s very easy! Before you buy, ask the seller about the condition, if there is a problem - don’t buy such a sample and find another. My 64s does not have such a problem.  

I read that if the vtf was hard to turn it would need to be cleaned and regreased

Did you have your cleaned and regressed?

I did, but only on my 66fx and only because the side panel fell off on arrival.
Look at the VTF spring of my 66fx with new grease.

My NOS samples of the 64fx are all fine, two of them. I also have 64fx PRO and it’s also fine. As you might know the fx series was made in the '80s and overall quality of some parts are better than old 64s from the early '70s.

The armlift and arm base are better on FX, dynamic tracking force is always in better condition that on 64s.
So the problem you are talking about is a common problem for 64s , but not for FX series.