'72 Econoline E-200 running rough - need help !!!

[EconoPower]

First of all, let me thank you for reading this post. I am a new Econoline owner, and couldn't be happier to own one of the coolest trucks ever made. (Getting rid of the '77 Dodge D-200 M890, as this van is such a better truck!) As well, I'm not the mechanical type, so I ask for your patience in reading this entry, and welcome your ideas.

I have recently purchased this '72 Econoline E-200, 302 auto with Air, with complete records from 1972-2006. This van was originally purchased from Ford by a Ford engineer who worked at the Lorain plant. The records are incredible, every time he got gas, any part, from where, how much, for 34 years -- incredible!! (Needless to say, mechanically it's like a new truck, exterior very close too)

The truck had been sitting for the past winter when I found her for sale, while with it's second owner son in law of the original owner. (Second owner put about 12000 mile on it, when his son drove it back and forth to college) Unfortunately, the record keeping stopped during this time.

At first, when I went to look at the truck while it was for sale, she wouldn't start, wouldn't fire. (The owner, not too mechanically inclined either, had purchased a fuel pump, but had not put it in) --->> A mechanic friend on mine came by, put in a new set of points and varoooom, fired right up!!!

The only problem was that it got hot after a short drive. (Never getting to the critical temperature, as it was shut off way before that)

So, a new thermostat and waterpump was put on. (During that time, since we were already there, we also put on a new belt, coil, plugs and wires)

It starts and runs fine, EXCEPT --- (Here is where I need your help....)

It runs rough when it gets warmed up. Almost like it's running too rich. It idles line, just when your put her into gear or hit the gas does she hesitate.

I drove it after it was delivered back to me with the new parts, when it was warm, and it stalled out down the street. Unable to get it started, I had to push her out of the street to a safer spot for the night.

Came back the next morning, and she fired right up, didn't even have to hit the gas.

Drove her home and left her idle for awhile.

After about 20 minutes, when I hit the gas, she hesitates a bit, and shook a bit, and revved up. (Almost like she wanted to stall again, but pushed though to rev up anyway)

I'm uncertain on what to do from here.

I have already added some fuel treatment, but haven't gone through the tank yet.
My mechanic says he'd drive this truck anywhere, as it's in as good of condition as anything he'd ever seen.
No leaks, nothing.

Only thing that needs to be done is the "doughnut" on the drivers side needs to be rewelded.

Please help me get by baby running like she ought to. Your experience is greatly appreciated!!!

Thanks !!!!