Nobody really asked but.......Open Forum Rules!!!!
After what I thought was a raging success I continued to have corruption on the LCD screen and I noticed it only happened during power up and power down. AC noise, the emissions from the tubes, something was dirty-ing up my signal line.
I tried to make myself as smart as humanly possible on HD44780 LCD's and sure enough the internets abounds with page after page of data corruption in 4 bit mode from motors, AC switches, etc.
I considered again dampening the 5vdc input with a couple filter caps then decided to try to wire up in 8 bit mode which according to the HD44780 docs is easily doable but nobody ever talks about it in Raspberry Pi Land because 4 bit mode is easy and fairly robust (unless you stick it under an unshielded tube amp).
I took a Raspberry Pi zero I had laying around and shoved it under the chassis (even though I'm not using the Pi Zero on the final install) and just put the LCD outside the base and tuned it on and off like 20 times with no data corruption.
Nice guy I am I documented the 8 bit mode wiring on a blog page with the appropriate code that needs to be added in lcdproc conf file (/etc/LCDd.conf) I'll tidy up the few tiny missing details later. A Pi Zero would easily fit under the crack although i have a hat board added to mine with USB and RJ45 ethernet. Anyway I want the horsepower of a Pi 3 for running LogitechMediaServer.
http://www.hagensieker.com/blog/page/?post_id=42&title=lcd-hd44780-raspberry-pi-8-bit-wiring