GMJim You might look to see if those guides have been knurled,that was a cheap fix for worn guides that in my humble opinion ruins them cause they'll wear right out. When the heads were young mechanics would beat the guides out with a big hammer,pound the new ones in !! Now that the heads are old,rusty,and fragile takes more care to change them. My last set I pounded out and pounded in new ones,ground them up and they are running,it is however possible to crack the head that way. To recognize the knurl look for a spiral groove clear thru the guide,also a little half moon notch in the top of the guide where they put their knurling tool in the guide. good luck you can fix it !! I've pressed em too seems like it is harder on the head than hammer method,never drilled any but on your 2 might be best rust and age are not friendly.
