Questions - Timing, Transmissions and Gear ratios

[Figuarus]

Hi guys, I know these questions get asked a lot, but I'm not finding answers specific to my issues/situation.

First and foremost, Timing. I've got a 283 with an Accel HEI distributor, A Quadrajet in need of a rebuild, and Camelback 192 heads. I unplugged the vacuum advance, and from what i'm reading, I'm sitting right at 14* advance while in gear (someone else was holding the truck in gear)

Does this sound right? With a stock cam, should I be sitting this high?

Second. My brother and I converted the truck from manual to auto. I've got a TH400 in there now, but while driving at highway speeds, It's screaming for another gear. I could go with a 700r4 or a 4l60e, but was wondering about going to a T5 or NV3500. I don't have the old clutch linkage or pedal anymore, however. Besides the pedal, do I need any of the rest of the stock linkage if I plan to run one of these manual transmissions? (I can easily find a clutch pedal.)

Third, What is the most common rear axle ratio provided in these trucks? I originally had an SM465 installed. I could remove the diff cover and get a real easy answer, but if someone knows what's pretty common, I would appreciate a quick answer.


thanks guys!