Tractor Repair: how to remove stuck valve lifters, valve lifters, cam shaft

Question
How id the best way to remove stuck valve lifters from a 504 utility gas engine? Also I have a 656 international tractor that I bought that gets stuck between 1st and reverse. What would cause this to happen. Thanks Roger

Answer
i dont know this engine but expect the best way would be to remove the cam shaft and tap them out with something soft like a brass bar or a brush handel and a hammer.I take it you mean the cam followers are stuck.
as for the international there is a good chance that the selector shaft for forward and reverse is cracked first inspect the outside linkages for any damage if there is nothing wrong there then the easiest way to check it is to remove the plate inside the left hand back wheel that the hydraulic filter is bolted onto(drain oil first) with this off you should be able to stick your hand in and feel around the top fo the gear box for the selector shaft you should be able to tell roughly where it is by where the lever goes into the gearbox.being mindfull not to get your hand jamed try move the f/r lever and check the shaft for craics if it is broken let me know and i will try to tell you how to replace it this will envolve a fair bit of ripping to mend