I am putting a body lift and coil spacers on my 91' sidekick 2 dr......what extended brake lines do I buy, currently it have the stock ones....thank you

Unless you're going with a HUGE body lift, you shouldn't need new brake lines. You'll want to take the left front line loose from the strut bracket and you might need to loosen the brake line bracket from the right side of the inside of the frame below the engine compartment, but you also might not need to. The other lines are plenty long enough...

it will be 2 inch coil spacers and a 3 inch body lift....do you know what ones I would buy if I need too?

you wont need to buy any to make it work. the stock lines are long enough, you just need to take the left front strut bracket loose from the strut and the fame loom on the right inside area of the frame below the engine compartment(this one is so you don't pull the lines apart while lifting the body, you can usually put it back once you're done...)

i got custom 3" longer lines made for the brake lines on the chassis to body. undo these before you lift the body.

the rear was good with 3" of sus lift.

the front, i just took them out of the fender/guards hole, and connected them up underneath the fender/guard. other people drill a new mounting hole towards the bottom of the fender/guard.

you'll need to mod your gear levers too for a 3" BL, and also fuel filler hose.

also check the steering shaft in the engine bay too when lifting.

for a 3" bl, you may need to lift the actual body about 5"-6" off the chassis to allow the body studs to come out enough for you to put the blocks in.

Just you be sure to put them back, and affix them away from the tires.  A buddy of mine had his brake lines wear through from rubbing against the tire.  They split when we were out on a trail.  We easily fixed it by cutting the line and stuffing a bolt in the end and hose clamping it down, but it could have lost his brakes at a very inopportune time.