trim/wake plate old boat

any ideas on how I can add a wake plate to this oldie? or should I go with one left and right. Looking to wake surf

its a 20ft south wind which is the same backend as a old barefoot. So the only flat part to the bottom is 4inch or so.
I could mount above the drain plug and have 12-15" plate but thats kind of odd but if it helps with wash it would be nice

A center wake plate can help control with the boat slammed. When you start putting it down, you will lose some push, but the boat becomes a lot easier to steer and porpoises a lot less. It doesn't really help with making a better surf wave, but it will make it easier to drive while loaded for surfing.
What are you trying to gain from it? Are you trying to do like a DIY Surfgate/NSS/Surftab system?
On an older boat you can surf just fine by loading it up with enough ballast. wake plates and trim tabs are not necessary for surfing.

I have 2500 pounds of ballast for it but it just always washed out. it doesn't porpoises really just rides high in the front even when weighted. Another funny thing is even tho i lisp the boat to surf side the other side of the wave is cleaner LOL
No one around me wake surfs so I am going at it with all newbies including me.

you can see with the design of the hull I don't know what would work best. The drain plug being there and not having any real flat spots LOL

I bet you could have a plate made that contours to the transom, then just have it fixed. It will help a ton on the spray. Easiest would be to attach it to the bottom of the hull.

That should definitely be enough weight for that boat. We regularly surf a larger DD with around 1500ish in the back.
First thing first, do you have a wave you can actually surf without the rope? If so, you have won half the battle.
Now if you are having trouble with spray, a larger swim platform will help block some of that, not too big or low that it interferes with the wake though. With the way your transom is stepped, there is limited area to mount one, but that width should be perfect and not too wide.

If you are having trouble with the wave face being clean, it would be best to post some pics to show everyone what you are working with.

When we surf the DD we have a 250 tube sack under the seat, a tube sack (350) on the surf side floor, this is about the same height as the rear seat. We then stick a 750 in the surf side rear seat where it's 50/50 on the seat and the tube sack. If we need to, we will sometimes fill up a 150 and stick that behind the dog house. This gets us a pretty good surfable wave that's clean. The hull is obviously different, but that's a good setup for a Sunsport.

Look at this guy's mastercraft install... he shimmed under the tab hinge to accomodate leveling the tab to the drain plug flange:

I'll shoot some pics when I get back out. it would get about thigh high but just all mush and wash
I had a 450 in front 750 in rear then surf side 750 and other side 450

Ditch the front weight. Ditch the weight on the other side. Put it all in the surf side corner. When you have a strong wave, then you can start playing with moving some around to different parts of the boat.
We had the same problem at first. At first we couldn't get a really good wake and it was mushy. This was because we ran the 250 under the seat, the 350 behind the doghouse and the 750 on the surf side of the dog house as well as a 150 in the bow. We struggled with this and then got the advice from wake makers to do exactly what I'm saying. Throw all the weight in the surf side corner, as far back as it will go and as much to the side as it will go, stack bags if necessary. When we did this it was like a light bulb went on and was day and night difference.
Even the seating of people makes a difference. A few times we have had someone move from the rear of the boat to the front while surfing and had the wake go to mush and drop us out. It can be that sensitive.
It matters how much weight you run, but it's more important where you put it. Start with everything in the far corner and then gradually start playing with weight in other areas of the boat to fine tune your wake.

With the size of your boat, with running 2400lbs of ballast you should have no problem with getting a strong wake. We are running about 1000lbs less in a 21' sunsport and have a good consistent wake. I'm not sure the size of your boat, but it looks to be under 21'.

its 20ft
we had it close to that but just with 2 older sacs of 500 each pulled to the corner but will do what you say and go from there. just last time my boat looked like it was doing a wheelie down the waterway

That's to be expected and also where the wakeplate comes in. It drops the nose a bit at the cost of some push, but makes it more stable to drive like that. Even with it, sitting down is not an option for us when driving and surfing.

yea I'm almost standing on my seat lol