225 Slant no spark

You cannot measure a ballast resistance accurately, and it changes as it heats. Measuring voltage @ coil is correct method. But back up. Run a jumper from BATT+ direct to coil+ (as told), then you get +12 V. You can run that way for 5 min and while checking for spark.

Check spark from the coil tower. That bypasses the distributor rotor. Do you have a spark tester (cheap at Harbor Freight)? Otherwise try to rig a real spark plug up to see or have your wife hold the plug wire 1/4" from the intake and jump when it zaps her, then look for a new wife.

Do you have a multimeter (free w/ coupon @ HF) and have you read the gazillion posts here? Worst-case, you could pull the distributor and spin it by hand to check spark. Ground the case to BATT-.