smoking/humming dynakit st 35

I'm not an electronics whiz but am handy with solders.
My Dynakit was running perfectly when I decided to upgrade its rca jacks and speaker binding posts with better ones.

After finishing such upgrade, my amp already had a loud hum and was smoking ( probably coming from the resistor). I have soldered the 16 ohm tap with a black wire as they were connected anyway in the original set up. I also just tightened the screws securing the tube sockets.

The tubes that came with the amp are not brand new though the seller said they tested fine. Is this a tube problem (just needing replacement)or something else? I do not have extra tubes to test it.

Many thanks.

A short between the speaker posts and the chassis will put the output of the tubes to ground. Be certain that the insulator blocks are installed properly and the heat from the solder did not melt something.

Check for solder splashes too, and be certain the arrangement of output wire from the transformer is identical as when you began.

I know it is too late to say this now, but a Polaroid or digital picture of the stock work is a reassuring tool when you must reassemble. I do this and draw a simple pictorial of what was original and what I plan to do. Sometime even marking the wires with small stickers from the office supply.
I concur with Albert - there is more than likely a short to ground on your new work. When replacing multi conductor terminations I always make a continuity map prior to starting work so I can be sure that I have not created any new paths in my work after I am done.