4 speed, Hard to shift when cold.....

My guess is either
A) the input gear is not slowing down because the clutch is dragging, or
B)BOTH the first and second gear brass rings are about done.

A) is easy to prove; just put the clutch pedal down and immediately try to shift into reverse. If it grinds this may be normal. Let the clutch pedal up and start over this time allowing about 3 seconds for the cluster to stop spinning. If it goes in now, then the clutch has enough departure. If it still grinds, increase the departure and retry. I don't like to wait more than 2 or 3 seconds with my oil recipe: 50/50 ATF/85-90 EP. So, if the departure increase and 3 seconds doesn't allow a relatively grind-free reverse engagement, then I'd be looking at the clutch.
B) But if it passes the above test, then yes you can try another oil recipe, but IMO and if it was mine; it would be time to pull it apart for inspection.Do it now before the points get all beat up.