Plug My Holes

Bro's P71 has some holes from removed equipment. 1-1/4 hole from a whip antenna surrounded by 4 screw holes, an 1-1/2 hole in the roof from the light bar, and 2 screw holes in the back of the deck lid.  

We first thought of stainless button head Allen screws and rubber plugs for the big holes. Then I found some white nylon plugs, that we could seal with silicone.  We also discussed plasti-dipping the black rubber plugs white. Besides welding the holes shut, ( not gonna happen anytime soon) any options I'm overlooking? He is in the middle of nowhere Montana,  so mail order is really the only option. 

rubber plug or silicone plugs.

Could screw in a kind of backer plate to the antenna hole, then use epoxy?  Would be able to sand it down and paint it relatively quickly

I'd worry that your other options would eventually degrade and leak.

Visiting in NYC, I had to street park a car with a CB antenna in the roof. My friends took one look at the car, and said that it was a break-in magnet with the antenna, so I was left with this problem after removing the antenna.

I needed a fast solution, so I stuck a bumper for a doorknob stop over top of it. I probably used some sort of additional sealer, silicone or something. Never leaked.

It was a long time ago; you can tell by the fact that it had a CB antenna.

The plan was to silicone the rubber plugs and screws to make them more or less watertight. 

Not an endorsement, but this company popped on to my radar when I was considering a PIU.

https://www.ebay.com/str/Nenno-Products

They have a number of patch products specific to retired police vehicles that look like domed stickers that are made to the right size. Some are application specific, so make sure you're looking at the right car. From one of their auctions, as an example:

McMaster Carr catalog "panel plugs" metal, plastic, nylon. Could probably use a little silicone under the lip for sealing. MC catalog has a variety of other style plugs.

Metal Snap-In Panel Plugs

Made of steel, these are our most durable plugs for panels. Tapered prongs snap into the hole to securely hold them in place.

Nickel-plated steel caps have excellent resistance to chemicals and salt water.

For technical drawings and 3-D models, click on a part number.

For screw holes I like to use a round piece of vinyl about the size of a dime.  

I would go to a vinyl shop and see if they have anything close in colour and buy it. 

Dorman makes metal (like the ones above) and plastic snap-in plugs.

Just browse the Dorman catalog at your local FLAPS and get what you need, along with a tube of Right Stuff black.

I second he McMaster Carr suggestion.

I put a piece of gorilla tape over an antenna hole a couple years ago and it still doesn't leak.

Well nut is what your looking for it will swell when you tighten the screw.

Aluminum tape should work.