Ok guys, thanks to help I recieved on this forum I decided to go ahead and complete the stable bias mod on my friend's DSL 100. This amp is a 1998 and has the JCM-02-00 board. I confirmed the bias drift issue on it. The bias was set to 78mv and over about 30 minutes of running I watched it climb to over 150mv and finally pop the HT fuse. Definately an issue. I went onto the Dr. Tube site and ordered the kit. The service was excellent, the kit was shipped within a day and arrived in less than a week from the Netherlands to the USA. In the kit we have the board, 3 standoffs, and I ordered the hollow drill bit to complete the repairs. It is not included but sold at the same place. Now, for the repair. Ok, so first. An inside shot of the amp, see the board in the middle? The one on the bottom? Yep, that's the one we have to pull out. When you remove it be SURE to label all connections. The rear board has 10 and the main board has an additional 26 connections.. LABEL THEM!!! This is the stable bias mod kit. The little white things off to the side are the stand offs which mount it to the board. The first thing, after you've removed the board is to disconnect pin 5 from each power tube. If they are touching the board then the stock bias supply will get to them. You have to disconnect this pin from the board. This is where the hollow drill bit comes in. Do this to all 4 tubes. Now we have to connect the wires from the stable bias mod board to the pins on the power tubes where we just drilled the holes. 1 wire for each tube (specific and listed in the instructions as to which wire goes where) 2 more wires are jumped to these resistors in the bias circuit. Now, we remove these 2 capacitors. Since we are no longer using the stock bias supply these are no longer needed. This is also where we are going to place the mod board. Now you can see the mod board installed in the lower left of the pic. It is where we just removed the 2 caps. Notice the wires going to the tube pins and resistors.(sorry for the bad pic) Finally, fully reassembled. You can barely see the mod board just under the big caps. Now, toss it back in the shell and ROCK! After doing it I must say that this is a VERY well thought out kit. It is extremely simple to install taking about 10 minutes of work. The removal of the board and labeling of the connectors took far far longer than the actual install of the mod. Great job @drtube. The bias is now holding at a beautiful 78mv per side with no issues.