94 200 zx transducer issue

i have an lms350a on my 94 200zx skeeter and i havent been able to get consistent readings from it since i bought the boat last year,,, i bought an LEI -hs/ws transducer for it and am pretty much set on mounting it to the transom SOOOO after i drill for the screws to mount the bracket what if anything should i use on the screws so they remain tight in place on transom??? silicone? epoxy?
i only asked because i looked where the 2 factory installed "thru the hull" pucks were and there really isnt any room down in that "thin" hull area,,, also kinda leary about trying to remove the pucks so this is why i prefer a transom install for this transducer,,, so what if anything do i use on the screws that i install???

I just removed a thru hull on mine, and all i had to do was tap it with a hammer and it came out clean as could be. No issues with the removal or installation of the new put back down.

If your dead set on mounting it on the transom, after you predrill, use good stainless screws and silicone all holes before you run a screw into them.