I am rebuilding a Rich Line Boat with the Serial #590042 and is a Model C that I bought about 25 years ago. It leaks badly and the wood in the transom is all rotted out. It has the drain plug hole. I paid $60 for it when I got it. I just paid $75 for a sheet of 3/4" marine plywood to rebuild the transom!!! I am having a hard time finding the 1/4-20 x 2" aluminum oval head Phillips machine screws that bolt the transom together with. Broke a lot getting them apart. I can find slotted round head and Phillips flat head screws but no Phillip oval head screws. I am thinking of going with the round head screws and using an aluminum washer and some silicone - what do you think? Thanks for your help.