Let's see,,,,,
If you do the governor then you won't need the midrange mod because the governor mods will take over all of that function.
I have no shiftkit in mine and it'll plant you back in the seat on the 1-2 shift at about 40mph at WOT.
My 2-3 shift happens at about 75mph at WOT, but I made internal mods to the separator plate and line pressure adjustment on the valve body.
If you do the governor then you can back off on the TP rod to make the shifts earlier if needed.
Keep in mind though, that the governor mod is only going to affect shift timing and not firmness, as line pressure and flow volume is responsible for firmness of clutch and band engagement.
With the power you are running the line pressure will need to be adressed so I would have to recommend a stage 2 shift kit first if you don't have one in it now.
You need to get the volume of fluid flow and it's pressure up first and see how that works for you first, then mod the governor to set your rpm vs shift points otherwise I have a feeling the power you have may cause slippage and fry the trans.
My mods consisted of drilling the separator plate to allow more volume and increasing the line pressure to increase speed of application and the ability to hold and not slip. (but I didn't care about WOT shift points like you asked about in your original post.)
I was more after low and midrange shift firmness with a bit of shift delay.
As a result I ended up with a nice firm 1-2 shift at about 25mph and a 2-3 at about 40 under normal around town throttle and will NOT go into third at anything under 30 even with my foot off the gas.
Again, my midrange mod alone will not change your WOT shift points at all.
The TP rod is only capable of changing it till it's at full adjustment as you found out.
Line pressure, flow volume and governor mods is what will give you what you want.
The shiftkit will take care of the volume and pressure issues and the governor changes will be responsible for the timing of the shifts compared to RPM's
Oh, I don't know about the availability of the bushings right off the top of my head for a console unit, sorry.
I think you may be right about the governor. I will read the article and see how that works. I need to replace the speedo gear anyway so I will be under it anyway. Oh and how about the what I think are nylon bushings in the shift linkage. I have the console shifter working much better, but there is still some play at the top and bottom of the shifts lever. Can you order those?
Oh and re the mod for mid throttle shifts. I would be interested in what you do.