spark problems

If you changed the resistor then you problem is else where.
If you not getting spark go on line and get the wiring diagrams for your Malory ignition.
Check it to and from the Distributor to the malory box and to and from the coil. Then check the ins and outs for power into the box out of the box into the coil and out of the coil and to the distibutor.You have to locate where your lose of juice is.