will this work?

will this cam fit into 1970 225 http://www.summitracing.com/parts/CCA-K64-246-4/ . the engine dident have hydraulic lifters before but this cam kit will add them. i was also planing on doing a overhaul kit from here http://www.flatlanderracing.com/rebuildkitschrys.html and was wondering if i need to go with the Mechanical or a hydraulic kit?
i dont want to buy all this and find out it doesn't work because the cam dont fit or the bearing journal diameters are different.
whats also the camshaft specifications for the bearing journal diameter between the 1981 225 and the 1970 225?