Hi, this will sound a little out there. I live in the UK where Firebirds are rare. I have owned 3 third-gens, two of which were medium green metallic 91-92 with T-tops.
The first one was mildly damaged following idiots trying to cause an 'insurance job' accident, then the insurance company agents accidentally had the car CRUSHED!
The second was bought as a replacement for the first, long restoration job to get it perfect mechanically and then cosmetically, and then some guy in a Range Rover tried to overtake around a bend and basically drove straight through the front of it, nearly killed me and my daughter.
In all this time, one medium green '92 T/A has come up, it looks mostly great, BUT it's a convertible.
I don't hate it but it was the T-tops I was in love with.
How are the convertibles made, and is it remotely possible to build a hard top that can interchange with the convertible roof boot/deck?
Many convertible cars have factory hard-top options, these might be fibreglass and are often the shape of the cloth roof. My goal would be to more closely restore the look of the standard car, when the roof is fitted, even if that requires removing deck lid parts and getting tools out to swap.
I'm aware that this would need to include fake sail panels, and its unlikely it will be possible to fabricate anything seamless looking that could lift the heavy rear glass of a normal hatch.
I'm happy to build something that can only be swapped with hours' work in a garage with a winch! It's not out of scope to build a replica with carbon-fibre layup and a polycarbonate rear window. I own a 3D printing business and design huge format 3d printers, so making formers is not an issue, the rest I have the appetite to learn.
What I'd love to know is if anyone has done any back-conversion of convertibles to hard-top, and what the special underpinnings are of a convertible that I could work with.
In extremis I'm considering buying this car if the price is right, and doing the research hands-on, see how it grows on me or not, and perhaps looking to trade for the same car but T-tops.
Any constructive thoughts and facts? Anyone actually done this or even just made a replaceable hardtop replacement for the cloth convertible?

 

With the amount of work required, I don't think your plan is a good idea. You want to take a fairly hard to find car and revert it to the standard body. If it's a good price, just get the convertible and enjoy it. You'll be surprised on how many compliments it gets.

 

So the goal is not to destroy what it is, a convertible. And the amount of work is relative - it's a whole, intact car and I don't intend to change that, if I buy it I will indeed enjoy it as is - I don't care about other people seeing it, this is quite personal to me. What I'm talking about is making a custom hard top for the convertible car, so that when I want to I can also enjoy the look of the original car. I'd need to learn new skills to do this - but at work I'm currently engaged in a project to 3D print bus body panels - formers for fibreglass or carbon fibre layup are not far removed and I will have a lot of the right materials and jigs at work.
What interests me here is what's possible. Can it be made to look good enough to justify the effort and be minimally functional and reasonably safe. I like a challenge.

 

You aren't going to make a convertible Trans Am look like a hardtop Trans Am and still keep the convertible functionality intact.

You could with an amazing amount of effort make it like a C4 Corvette convertible with the removable hardtop option.

I actually think a C4 Vette with the hardtop installed looks way better than the hatchback Targa top Vette and it for sure rides better.

 

I thought of doing this way back, but decided not to. Simply because im older now and would rather drive and enjoy it, but if i was my younger self 30 yrs back id do it. You already have the top frame. My idea was to used the original top frame, just lock it in place by welding/riveting joints and removing linkages that wouldn't be needed anymore. The use the soft top as a guide to form sheet metal or fiberglass panels, but the skin would end up as one single piece. The back window has many options from all sorts of cars. Id want a defroster and i would've integrated the OE overhead console and also use the vert headliner as a pattern for a new headliner.