Trouble taking off (plenty of power..) ???

[bowtiedriver2]

Problem:
When I try to take off in first gear, the truck wants to die. It seems like it is trying to choke out. I have to take the engine up into the 2500 RPM range or higher before I can really get the truck to take off. But, dropping the clutch at 2500+ causes me to spin the tires everytime. I should have plenty of power to take off from damn near idle. Any Ideas???

I have a 350 that has been modified with a high lift cam and holley carb. I am sure it is overjetted just not sure by how much (bought it like this). I think this may be contributing to it but I have not had alot of experience on carbed motors.

The trans is a saginaw 3-speed that has been converted to floor shift. (sucks but works for now)

Why can't I take off reasonbly without it dying?