Ok your issue was it wouldnt run off of choke.
That points to the EMALSA TUBE. Its the long small one with all the holes around it. 90% of the time that is Dirty and plugged.
Your saying the New carb has No adjustments ? I have Never seen one with out some sort as that is where thay put the Ports in it. Now I have seen some that have plugs sealed over them.
Lets step back and punt here
1, Runn it with out the gas cap on. 2, pull the fuel line off the fuel pump ( pump to carb) and crank it over .( put a longer hose on the pump into a jug) Check flow. 3, I have seen this in the shop
Check and make sure the fuel line DIDN'T get pinched between the upper and lower body. 4, Check you oil level and condition. It should be 10w-30 or better. And 2qrts or less.
This all is for a LEAN FUEL condition. NOT Weak spark.
Hope this helps and if you need you can PM me and i will give you my # so you can talk to me.