From my own personal *biased* opinion the engine would have to be able to crank ( i.e. not seized), the turbo would have to do the same, hopefully try to fire with the aid of some starting fluid up the intake snorkel. Expect the alternator to be seized, the coolant pump may be in the same boat, a careful inspection of all the plastic vacuum lines for their condition, the coolant hoses would need replacement, etc.
Expect to replace ALL of the brake components...calipers, rotors, flex hoses.
With regard to the PMIII...the master assembly is mounted to a firewall support that is not the same one used for the non abs system, if one wanted to convert the entire PMIII brake system to vacuum boost one would have to locate a regular non abs car in a salvage yard & go to the effort to disassemble all that is needed to pull that support to install into your project.
The chassis would have to be in really good condition, the paint the same......even then, if the powertrain needed an entire rebuild then in reality what you're purchasing is just a rolling chassis & would have to priced as such & the present owner understand that.