I hear a lot of people complaining (non-Caddy people) about how with a POS engine like a Northstar, you have to tear the engine apart to get at the starter. Mechanics especially.
1. It's as simple as removing the intake manifold and
2. You don't need to remove the intake on 95-99's.
I just replaced one on a '98 STS and made record time (for me). 45 minutes start to finish.
How? Leave fuel lines connected. Leave the heated TB hoses intact. Brake booster vacuum line left intact.
Simply remove the intake bolts, the ground wire to the fuel rail, remove the bolt holding the fuel rail to the coolant crossover, and prop the one end of the intake up by the P/S pump. With careful hands and small tools you can have the starter out in 20 minutes, without damaging anything. Of course, disconnect the battery first.
All you have to watch out for is the intake ports- don't let any dirt, debris, or small parts fall in. And don't let the fuel rail/lines kink anywhere.
I've heard labor times of up to 9 hours. The day I'd pay someone $900 labor to replace my starter, is the day I will declare insanity.
Just a note to anyone who may need this done in the near future, beware of shops who charge too much (GM techs- I know the dealerships set standards and I'm sorry if I'm offending anyone)- if you can't get quotes of 4 hours or less I'd say take a bit of time after work and do it yourself. An unexperienced individual could easily do it in 2 hours.
The guy I changed this starter for had his alternator replaced in St. Catharines Ontario and it costed him $1400.00. Liquid cooled, a bit of a pain, but still an insanely high price. I don't like to see people taken advantage of.