Gemini 1988 bass boat Cleanup

[football004800]

I have a 1988 bass boat. It has to many problems to post multiple threads about so i figured id place it here. I am new to bigger boats like this all my boats prior to this were hand tiller. so its new. Ive so far rewired both fish finders, the lights, carpet work, livewell fixed and so far thats it cus thats all i no how to fix so far. I am need helping and advice from anyone will to give me any. alright underneath the boats there are some scrapes. there is a big srape also, witch is pictured, how should i go about fixing this? also how do you paint over it when i fill it in? My next problem is, my speedometer doesnt work, it powers on and everything but doesnt pic up speed. also how should i go about rebuffing it and making it shine its a lil faded.