Pinsider "Rubberducks" had suggested I come up with a solution to get rid of the ugly, visible switches in BSD and this is what I came up with. I likely went overboard with it and spent way more time than necessary, but I'm happy with the results .
YT description: This mod interacts with standard left ramp shots when the ball goes under the Elizabeta tombstone, right ramp shots as the ball passes under the castle grate (as Hellsing Speaks), triggers off of each switch hit during Rats bonus mode, whenever Hellsing speaks (castle multiball, etc.), successful skillshots, and so on (anytime the castle/Hellsing flasher lights).
To get the stained glass look I use 3 LEDS (R/B/G [creates the appearance of ~5 colors]), as well as multiple layers of light diffusion, and of course the painted window insert.
The circuit (capacitor) on this mod creates a nice fade effect for the LEDs (the standard, fast blinking didn't look good to me here, so I experimented with the breadboard and various capacitance values until I got the desired result).
Both the castle and tombstone install very easily and quick with the factory screws. The skull mound also installs easily with the factory switch screws (replacing the old switch cover clip). The old cover remains in place for the castle, but the right side cover is removed for the tombstone.
Both the tombstone and castle have voids for the switches to rise into...failed that aspect on my first design, ha ha (neat effect on the castle grate as the switch can be seen rising up behind the bars--don't blink ). Also neat to me seeing the ball pass around the castle/skull walls and zig-zag through the arch, but then again I may be a child trapped in a man's body...
I made a point to not obscure any features or lights/inserts, etc (from average adult height while playing).
Skull was made roughly to scale with Drac in the coffin.
[while there is some space available between the skull mound and coffin, I'm not certain if it fits with the Brock/larger coffin mod or not--if it doesn't appear that it will to those with that mod, I could potentially make a revision to have a version that does]