Need help locating vaccum leak?

[Alvin]

I'm pretty sure there is a vaccum leak causing my truck to stumble and sometimes die when I stop. The truck only stumbles when it warms up, and I am stopping at a light or stop sign, and I leave the tranny in drive. If I bump it into neutral, the engine recovers. So I'm thinking it's somewhere between the engine and the brake booster...but this being my first truck (and my first real V8 vehicle), I'm clueless. I've researched all the other stuff, but common engine malfunctions just never came to mind. So any help on isolating the location of the leak would be very helpful. Also the engine burns a lot of oil on startup and at idle. It's not the worst smoking I've ever seen, but it really makes my truck seem like an old beat up farm truck, and that's not the image I want!! I'm just looking for some opinions before I send it off to the mechanic. Would love to be able to fix it myself though.

I know I've said and asked a lot here, but I need help. I drive the truck everyday, and for now it is my only vehicle. It could be out of comission for at most two days, and it seems to rain every other day. Thanks in advance for any help. My dad doesn't get back from AZ until Tuesday, then hopefully he can help me fix it. But like I said would love to be able to do it myself.

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- Adam L. Vogel
University of Cincinnati
White 68 GMC short, fleet, 350/TH350, 67-8 chevy grille, 5-lugs, front power disc brakes, power steering, a/c (not complete yet)

My truck site
IM= newt0