still trying to figure this out!

[86 K-10]

im trying to decide what my next step should be towards figuring out my "no power" issue. the situation: just installed my rebuilt 350, first test drive felt like there was no fluid in the tranny.."marshmellow peddle". the tranny is full of fluid but is definitely shifting wierd, shifts really fast into 2nd then the motor just winds out into 3rd. shifts arent firm at all and im just getting nothing from the peddle. it does shift through all the gears and into OD, and downshifts from OD to 2nd. i dont have a pressure guage and i dont know anyone who does so my only real option with the tranny is to take it to a shop (last resort) or just drop another 1300 this month on a new one(not an option at all lol). oh, TV cable is properly set...correct geometry and all that jazz. torque converter is properly installed as well.

im scared to do an actual WOT run since i still havent broke the motor in, so it's hard to say this is all tranny.

the motor is honestly running and idling great, i absolutely installed the timing gears correctly, i've rechecked the dizzy location, firing order, and adjusted the timing...carb seems to be getting plenty of fuel, i cant fathom this being a lack of power from the motor.

here's my motor setup:

'85 350 block with .060 overbore
hypercuetic pistons, 9:4 compression w/ standard head gaskets
cam... i dont remeber the exact specs but it was something like .44 intake, .45 exhaust
stock crank
stock vortec heads
holley 600 vac. secondary, elec choke
holley 80gph fuel pump
jegs 331 high rise intake
comp cams magnum roller tip rockers
summit hei w/ 50k coil
msd street fire cd ignition
headers (biggest PITA of my life)
2 1/4" dual exhaust with glasspacks

tomorrow im getting a vac guage since mine is still being "borrowed", i'll post the results. in the meantime, I NEED IDEAS!!!! PLEASE!