Electrical Work....

I have recently purchased a 1981 Sea Sprite 18' open bow... I/O GM 3.8 120hp motor on it with an OMC outdrive. I have yet to take it on the water because I cannot find the partz I need at the local marinas and stores.

First off, the problem: There are 5 Celenoids on top of the motor 2 of which are for the trim and 2 more for the 'high tilt' of the outdrive the 5th one I have no clue about. The trim of the motor was working however, the 'high tilt' was hit and miss depending on the day u tried the switch. So to prevent problemz on the water, i decided to replace the one celenoid that was bad (after testing them with a multi-meter, post to post) replaced one, and got nothing (not even the 'click' i had before) so after consulting a few mechanics they said i would be better off replacing all of them then going from there to make sure i got the right one. so after that, i can no longer trim anything, and the motor will no longer even crank. I got the celenoids from the local auto parts store (autozone) and after replacing them, i was tld that marine celenoids are different from car celenoids (is that true? and could that be giving me this problem?)

Now the question: Would it hurt anything to re-wire it all down to have 3 celenoids? one for the trim one for the 'high tilt' and leave that 5th alone? and does anyone know of where i could find a wiring schematic of which wires are which on these celenoids (and the rest of the boat) so i don't have to pull everything off and re-wire it all.

Also, when purchased, I was told a head gasket was bad, however the oil is not milky, there are no air bubblez, and the engine seems to idle/run fine (with the water muffs on) is there any other way to check it without tearing it all apart?

Thank you much in advance....