Just wires in place of one resistor (unsure about which one on the DSL), and drilling holes to mount it. Non- polarized so doesn't matter which lead goes to which spot. Which size are you looking at, and what are you looking to gain from it?
Yes, you need to know how to discharge the caps so there's zero energy on the board before you work on it.
I did it to a JCM 2000 60 watt combo. Didnt make a diffetence because the power section is made to lay down.. I put a big Output Transformer on a 30w 4-EL84 cathode biased combo and it blew everyone out of the room.
sound like it’s simple enough you could do an a/b test before you commit to drilling and installing. Id be interested to see if you hear a difference. Ive heard the choke improves the feel of the amp