90 volvo 740 turbo

It'll probably run, but not very well, and since the turbo engines are low compression you'll be left with far less power than the N/A version had so even if it works it's not safe to drive it like that. Just have the turbo rebuilt, or sell the car to someone who will and get a NA model.

You'd need a front pipe as well as having to adapt the smaller diameter front pipe to your catalytic convertor, and extend the wire for the oxygen sensor which will have to be repositioned. You'd have to plug up the oil delivery and return orifices in the block. You'd need to figure out some way to get the air intake pipes from the air mass meter to the intake manifold. In the end, you'll probably end up spending more and end up with a much poorer car than if you just replaced the turbo.