I have a 1998 Volvo S70 Turbo and it is making a squealing noise right after start up, is my turbo going bad?

SOURCE: 1998 volvo s70 distributor leeking

just remove distributer knock roll pin out holds bottom gear on remove bottom gear pull shaft out of dist. housing replace o-ring seal and reassemble, not really that hard

SOURCE: Do I need to remove the dash to remove a heater

Don't remember exactly , but I think it could be done without dash removal.
It's done from driver side footwell area , tight but possible.
You have to take out lower center consol side cover , next to the accelerator pedal and roll the carpet out of the way, and you will see the heater core case. Remove cover on the case (some have it on the side , some on the bottom).Two pipes going from firewall to the core have to be disconnected before core removal (will leak coolant , have some rags on the floor to absorbe it).
Slide heater core out , put new one in gently as the accelerator pedal is on your way , try to avoid damaging core a lot.
Always replace heater core pipes o-rings.

SOURCE: Where is fuel filter on 1998 Volvo S70 non turbo?

the fuel filter is located underneath the rear passenger seat next to the canister box (the canister looks more like an air filter box housing. All you need is an 1/2 inch key to loosen one screw and pull on one end of the hose/tube to release it from the fuel filter. Pull opposite the unit. your best solution is to look to buy it on line so you have an idea as to what you are looking for then check against the info provided to you. I just did mine 15 mins. next to the rear tire. You will need to jack up the rear tire for easy access