purchasing a 1965 gmc 305v6 truck

[Ianmattchevy]

Hey guys and gals i am tempted to purchase a 1965GMC 305 v6 ( not an inline ) it has 3 on the tree manual all original with 90k miles. I went and checked it out and it starts and idles beautifully and not drips, not much rust at all. Looks like the tires have a bit of cracking so i am not so sure how fast i can go and still be safe. My question is how are the trannys on these things and also what is the gearing...will it go highway speeds? It has the original air filter ( that takes oil? ) ....what would be one of the first things you would upgrade on this truck to give it better gas mileage and run better.. I am thinking carb ( whats the best kind ), plugs/wires, air filter unit, syn oil change, dist cap....what else? any comments would greatly be appreciated...I am VERY excited to own such a cool classic but I want it also to be a almost everyday driver and be able to hit the freeway here n Cali. I live in woodland hills and can anyone can recommend some shops in this area that specialize in older trucks and cars? Thanks so much.