Working on my 56 Buick Special. The wiring has been fouled up pretty badly by previous owners. After a long electrical diagnosis (in the 90 degree heat) I have come to the conclusion that my starter relay isn't functioning properly. Unfortunately, I can't find a replacement online or in the stores. Would it be possible to use a different relay in place of the original starter relay? For instance if I just went down to the auto parts store, slapped the old relay down on the counter and told the kid behind the counter to find something that looked like it? Thanks for the advice.