Removal of pipe plugs (oil / water) - 289 Water drain - Located under the rearmost exhaust port on each side - )Remove Starter, oil filter ( on full flow models) )Standard Studebaker Drain plugs have a 7/16" square head and will fit nicely into a 1/2" - 8 point socket. In the event these have been replaced with a later version that has a 3/8" head, then use the female end of a 3/8 socket extension, with the male end fitted with a 3/8 allen head socket. The head of the 3/8 allen socket can be mated with a regular 3/8" socket with a ratchet. )You should first wire brush the area to clean any surface crud away amd use a good grade of penetrating oil, letting it work for an adequate amount of time. Oil gallery - On one end of each head are 2 small plugs sealing off the unused access ports to the oil distribution system. If these have to be removed, clean the area, soak with penetrating oil and use a large size Tap T- handle, tightening the vise bit of the t - handle over the square head of the plug. These tap handles usually have a 3/8" socket fitting on top and can be used with a ratchet to augment the twisting force. Works every time... BobJ