Advice on 306 to 347 trade

[QuantumMotorsports]

Okay, here's the deal. I just built a 306, forged pistons, stock crank and block. GT40P heads, weiand stealth intake, comp cams magnum 292H, did all of the work that wasn't machine work myself. Just finished putting it in the car. Then my uncle tells me he has a friend with a running 347 setup that he wants to trade for something more streetable. He wants my 306. I don't know many details yet about his setup, but a 347 sounds really tasty. Then again, I just spent a good portion of my time building this motor and putting it in the car. It's not running yet, just setting in there, but I feel kind of attached to it. What do you think I should do? Once I hear some details about the 347 setup, I'll post them here.