Carburetor + Transmission Question

[patriotgames65]

Hi there. Hoping someone can give me some insight to a couple of concerns I have going at the present time. I'm just a dumb welder, so please use lay-mens terminology if responding. And thanx in advance for the help/input.

I recently purchased a 79 GMC High Sierra in fantastic shape but with all the general things that go wrong on a 30 year old truck. When it comes to u-joints and such, I'm good to go. Get much deeper, and I bog down.

Ok, the truck was originally equipped with a 400(vin # decode) but now sports a swapped in 350, at least, I've identified the heads as 882 series heads but have not been able to id the block as of yet. # stamped on pass. side head under the Alternator does not correspond with any decoding info I have been able to locate on the web.

Motor is equipped with an Edlebrock 1406 series carb, Edlebrock intake, run of the mill rusty as hell headers and farm boy dual exhaust with generic glass paks. Additionally, the truck has a 4 inch lift and 33x12.50/15's.

This truck will be seeing duty as my daily driver and of course, I would like to find the best power/economy ratio that I can achieve. My 1st question is this, what would be the best metering kit to put into the 1406 to lean it up a bit, but still maintain a respectable amount of power? Any Edelbrock experts out there?

2nd question: When accelerating from a stop, when the transmission shifts, it shifts into 2nd very quickly. I would say within 2-3 seconds of appying the accelerator. Then the transmission winds up considerably, and I have to "feather" the accelerator to get it to shift into 3rd. I know that it could be any number of things, but my question is, what would be the first thing I should check, second, etc. etc. short of cracking the tranny?

Again, sorry for the long post, and thanx for any help you can give.

Kevin