Our boat did not have a TV, We added one. Went with a 22" HD 110v and added a power inverter. As cheap as little TVs are any more. Buy what fits your budget and install. If you need to add a power inverter, also fairly easy, but buy a true sine wave as it produces cleaner power, will have less static on screen. But if you search a little, 12v can be found just about everywhere also.
Do a search on either topic. Should find more than enough info to get you going.
As for antenna, can not help. Other than, start pulling things apart and figure it out, thats what I do.
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2000 248 5.7L DP
'92, '94 SXI 750, '08 STX 15F, '12 Ultra LX 300
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