Itsbitse wittle wed fuse
The fuse that looks like a bulb is in the instrument housing.
It is reached by removing the instrument housing.
If you're agile you can pull the housing far enough backward to dis connect the speedo cable then you can have enough hand room to reach it.
I would suggest removing the housing.
Then with the red rascal in hand, solder a length of 14 or 16 ga. twin conductor to the two connections on the fuse holder.
Replace the red bulb into the housing with the twin lead routed through the lower portion of the dash and out by the brake pedal area.
Replace the instument housing.
Remove the carpeting and floor insulation, and route the twin lead into an area convenient to reach.
Cut the twin lead to length and solder a mini-blade fuse holder to the ends.
Install a mini fuse, I don't have my Owners Manual in hand but the same as the OEM.
When I had my speedo repair I spied that little red rascal and I knew I wasn't going to remove the instrument panel to get at him.
If you have to reach the S/S voltage controller that's a good time to make a bad design good.
Happy Trails Beep Beep from Houston
Donald, El Cheapo