I had nothing but problems running the Melling HV oil pump. I t wiped out 3 different cams and distributor gears. I switched to a standard volume pump and never had a problem since
MBHD
The two cams were Clifford's and one American camshaft all new distributor gears were installed.
If you insist on using a HV oil pump I would install a bronze distributor gear so it won't wear out the camshaft, but the distributor gear will need replacing after it gets worn, but it will save your camshaft.