i recently installed black lights in my bonnies but wasnt really satisfied with the results.
i need to know what could be added to the interior that the light could reflect off of, but would also still offer a simple and factory installed look

You could put reflective tape all over the place...

you could put the reflective tape to the side of the tube that is mounted too.

well black light doesnt reflect a visible light really... you need white things or glow in the dark things. Certain white things will glow purple ish and anything that glows in the dark will glow BRILLIANTLY.

ok heres what i did w/ my truck, i will find the page but a company makes a paint that is CLEAR but it will glow different colors in BL depending on what color you order...
as i recal its not cheap.........but it IS out there

Thank you i would appriciate that, by the way i just ordered that plasma glow multicolor underbody kit too how is it can u see the leds in the days too

well....
when you get them on the car, make sure you point the LED'* OUTWARD like NOT at the ground.... like off to the sides and it will glow good.. they kinda remind me of christmas lights.... how much did you pay for them? also MAKE SURE YOU FILL OUT UR WARRENTY ASAP!!!! trust me YOU WILL need it.. ive had the kit since May, and ive already fried 2 control boxes.....

I paisd 300 the msrp on them is 400 i got them on nexxon.com