Be better to use the NCT Taxi line so it's on their system as a taxi and also tell them in the NCT centre the day of the test cos sometimes a two Yr cert is produced which won't suffice for the NTA when they check that before they'll give you a date for the SGS.
My last 2 Cars (since 2012) were always Taxed and NCT'ed as Private. Never an issue with Licence renewal , or initial suitability. The local SGS Taxi Guy (who can be a pr!ck when he wants) told me that as long as the Car has had an NCT Test passed within 90 Days of renewal it doesn't matter whether it's marked as Private or PSV.
The main reason I did it like this is because I used the Car for Towing a Transporter to Motorsport Events, and wanted it to be Privately Taxed to avoid any issues with the Guards. The Private Car NCT also meant I didn't have to ring the NTA to book a Test....I could just do it online whenever I wanted.
I'm gone Electric now since March, so I had to change the Wife's car to something that could tow my Transporter......but I'm still going to keep the Tax and NCT as Private on the new Car. It's only a Tenner more to Tax it for the year.
A friend who works in the NCT Centre told me that it's up to me if I want to put the Car on the PSV system (he was only letting me know in case some NCT Tester decided it was his job to change the Car's classification).
Technically, you can be done for No Tax if you're using a PSV Taxed Car for Private use. Rarely going to happen, but all it takes is meeting a Gobshite Guard who's having a bad day
