Jerk and stall when put into gear?

Hye guys,

I recently picked up a 66 Valiant 100 with a 170 /6 and have been slowely working my way into turning it into a driver. The car didnt run under its own power when i bought it last month or so. After rebuilding the carb and re-adjusting it/timing it I cant seem to get it to run correctly once in gear. The car purrs like a kitten at idle when in park and neutral. The second you put it in R or D the tranny slams into gear, the one wheel sqwauks, the car moves about 2 feet and it dies. It'll always crank back up and idles and what not right after. The one or two times i got it to move(drove about 4-5 blocks) i had almost no acceleration and constant backfires ect. The tranny fluid is at the correct level, it has fresh fuel, ect.

With these symptoms what do you think could be going on. Theres no telling how long the car sat prior to me getting it and theres no doubt that its long over due for a tune-up.

-Jake