Hi. I have a 1953 NAA ford jubilee. The tractor runs well for about an hour. After that it starts to lose power and the engine starts skipping. Checked the timing and firing order. All seems correct. Runs and idles great when cold. I have replaced the points, rotor, condenser, distributor cap and cleaned out gas line and filters. I had tried to convert it to electronic ignition but swapped it back because i couldn’t get it running smoothly. It does have a history of going thru points quickly. Any advice onvwhat to check next or what the problem may be would be greatly appreciated.