I have not had the screen in the 993 done,, but have had different results with autoglass,,, they replaced a screen in my old 944 once and made a perfect job, it was done in their depo and they had the car all day...
had one of the mobile guys replace a side window on my volvo,,,, it nearly fell out the next day,,, they sorted it and then the window would'nt fully open,,,,, eventually someone else came out and sorted it....
suggest that if you do use them, you request someone that has had some previous knowledge of porsches........ not some spotty 19 year old, that's used to fitting screens into ford mondeo's
let me know how you get on,.,.
cheers
scott...
a thought though,,,,,, autoglass guys probably fit more porsche screens than your local opc,,,,,,,, if you can get the right person !