Cut a top off ‘90 model?

I can buy a ‘90 Power Ram, short fleet side bed, 318, 4 speed, 4x4. The only real down side is the roof about 2” above the windshield is rusted out.
I don’t want to graft on a new roof. What about cutting it off and leaving it off. Take out the back window but build a cage and leave the windshield? Maybe even remove the doors.
The truck was originally a state vehicle. It’s white. The rest of the body just has surface rust.
I passed on it but later tonight got to thinking about the open cab.

I am not a big fan of a topless truck, but it is yours to do as you please.

Why not? Another option is a hard top convertible.

Alright. So let’s back up. The body is far better than average. Looks like all the sheet metal is original with the white original paint.
If a donor roof is welded in then that throws off the look of the truck as well. Another cab throws it off even more.
Short bed, 4x4 manual trans has me interested but I just don’t know about the roof rust.
What is a reasonable solution without spending too much on it?

The roof panel is two layers of sheet metal, are both the outside and the inside rotted through?
Cheap fix?
Cut out the rust and weld in a patch? Body work & paint optional.
Fiberglass, kitty hair, bondo and paint?
Drive it and forget it?
Gene

There is visible rot through the inside panel above the passenger door.
I think it would be a fun truck to drive and work on providing the seller is being straight with the details. I’m 80% sure he is.

Another question- more in general. How much of this truck would be electronic? It is still factory EFI. How tough would it be to go backwards in time with it and make it more old school? Just in case stuff is jacked up.

I think that would be harder than cutting the top off. If the EFI system is jacked up and the roof is rotted, thru it's a parts truck.
As for going topless, I would look at a pop top Ramcharger to see how to finish the pillars. Add a roll bar in cab and maybe see about a homemade soft top.

Grind away as much rust as you can, treat it with anti rust inhibitor, then fiberglass and then filler it. Primer and paint. We did that to rusty muscle car roofs when they were cheap cars ack in the day. You could do it in a weekend for just a few hundred bucks.

There is actually 4 pieces to the roof. The drip rail, the outer panel, the inner panel and a header panel sandwiched in between the inner and outer panels. There are about 257 very randomly placed spot welds holding the whole thing together. You can't buy any of the pieces new and most used stuff has some degree of rust. When I did the roof on my 92 I had found a pretty clean roof from a parts truck but it had some rust through right at the windshield flange. After drilling the spot welds and removing the drip rail, header panel and outer skin from the donor I had 3 pieces of swiss cheese. My inner panel was still solid. It was a PITA and I don't think I want to do another one.
As for the fuel injection that should be easy. You need to regulate the fuel pressure down or replace the pump to something carb friendly. Intake manifold, carb, distributor and ignition box should get you up and running. You may need a wire for the a/c clutch and bypass the ASD relay to get the fuel pump running but that's about it.

Could you use the wide metal tape to cover the rusted out section?

Guitar’s info doesn’t get me real excited about tearing into this thing. I just want to drive it. Maybe slapping a piece of tape on it is the way to go. Maybe I’d be fortunate enough that the windshield frame hasn’t been too compromised.

The tape won't stop it from rusting. They rust from the inside out so unless you either cut it out or drill holes to spray some rust converter in there it will continue to rust. With the way it's put together with the inner header panel it's doubtful you would be able to get it all coated.
I had some pics from when I did mine but they were on a phone that died so they are lost.