A stripped air fuel mix screw has nothing to do with the petcock valve.  

The stripped air fuel mix screw is discussed in this recent post.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1730160337

The raptor petcock valve will work beautifully with a VM36.

You have a stock Mikuni CV (constant velocity) carb (BS40ss).  The VM36 is a slide carb (totally different animal).  It’s not plug and play.  You need a different throttle cable for the VM36, or modify the stock cable to work.  And you’ll have to make a different air intake snorkel or use a pod or cone air filter mounted directly to the carb.  And you need to know how to tune the VM36 carb.

Based on your questions, I suggest learning how to fix the stock carb.  Read the post I sent a link to.  There are other links to more info within that thread.

Welcome to the world of savagely dirty carb problems on cheap 2nd hand fixer uppers.  So many of these bikes are savagely passed along from one newbie owner to the next and are abused and unloved.  Give it love and it has hope.

Suggest reading everything in the Carb section here —>

http://suzukisavage.com/home/tech/fuel/

JOG - when was the last time either of those bikes/carbs were used and running?  Haven’t they both been sitting up a while?  While they might be jetted right, I’m not sure the air/fuel mix screws on your carbs would move either.  They both probably need a thorough cleaning, right?

Right...Buyer beware?

Relax dude!  I'm not saying any of that.  And I'm not apologizing for whatever offended you.

Your check is in the mail.  You should have it no later than Saturday (probably tomorrow or Friday).  As I told you, a couple other parts sold and rather than sending multiple checks, I held off and wrote 1 check.  

Nobody is saying you are greedy or not honest.  I just think you need to be transparent especially with a newbie that's having trouble getting his bike running right and clearly doesn't know much about carbs.

And I have thanked you for our business arrangement.  I thought it was a mutual agreement and I drove over 200 miles to make it work.  Let's take this offline.  PM me if you want to discuss further.