856 fuel starting quandary questions

[FLtractor 162]

Evening,

 

Went to start 856 today after new battery.. old then brand new non ethanol fuel.. brand new fuel lines.. filter.. electric fuel pump.. new aftermarket carb.. newly wired and brand new ignition.. has spark.. but tractor wouldn’t even attempt to run other than just turning over from key.. issue most likely the carb needing fuel and air screws adjusted keeping it from running? 
Also noticed fuel leaking from the brass fuel pump fittings (ideas to stop this fuel pump leak? Never had fuel or even been hooked up and ran from battery before- first time ever) and from newly replaced under tank fuel valve.. and noticed a liquid (fuel?) every so often dripping from the muffler, just a drip every now and then when turning key attempting to get started with engine turning over but no combustion happening. Why would it be dripping from there? 

Edited 2 hours ago by FLtractor