led's and car alarm output

so i was reading https://www.the12volt.com/installbay/forum_posts.asp~TID~119771~PN~1 and my idea is basically the same but alot more simple. my setup is LED's in the door handle, i read the idea from here, but no follow up or tut was made. basically atm, i have 4 LED's i found from my 10pk. gonna try to find 6. they are green, 2Vf @ 19mA, sadly 19mcd, not bright, but this is an idea, so if it works ill up the Candals. i have 6 1/2watt 560ohm 2% also 6 1/2watt 68ohm 2% resistors to hook up to them. since its a car door, im looking at ~12.8Volts. there will be 3 per handle, (2 handles) independent wired. as u can tell. so now the fun part, i want to wire it up so it uses a capacitor as the pwr src. and stays on for ~30seconds and of course, will semi dim out. the main problems/questions are: 1) for a relay (SPDT or SPST) do you think my alarm unlock signal will trigger the relay to trigger the cap? 2) how big a cap i need per side? lots of reading. summarized, 2Vf@19mA LED with 560+68=628ohmR @ 1/2watt with 12.8v pwr src. times 3, how big a cap about to keep the 3 on for about 30seconds? im toying around with simulator but it has it limits, much help needed. TIA ~wolf

so through the java sim, if it's close to Real Life, i have it at about 200uF capacitor. here's my diagram for one handle, the switch is my alarm unlock signal. $ 1 4.9999999999999996E-6 10.20027730826997 49 5.0 43 178 144 48 144 160 0 1 0.2 -3.521627434110996E-17 0.05 1000000.0 0.02 20.0 R 544 16 592 16 0 0 40.0 12.8 0.0 0.0 0.5 g 560 448 592 448 0 w 544 16 144 16 0 w 144 16 144 48 0 w 144 16 112 16 0 w 112 16 112 48 0 w 64 48 96 48 0 s 64 48 64 176 0 1 true w 64 448 64 240 0 r 128 224 128 288 0 560.0 r 128 288 128 336 0 68.0 162 128 336 128 384 1 2.0 0.0 1.0 0.0 w 64 240 64 176 0 r 176 224 176 288 0 560.0 r 224 224 224 288 0 560.0 162 176 336 176 384 1 2.0 0.0 1.0 0.0 162 224 336 224 384 1 2.0 0.0 1.0 0.0 r 176 288 176 336 0 68.0 r 224 288 224 336 0 68.0 w 128 208 176 224 0 w 128 208 224 224 0 w 128 208 128 224 0 w 128 384 128 448 0 w 176 384 176 448 0 w 224 384 224 448 0 w 64 448 128 448 0 w 128 448 176 448 0 w 176 448 224 448 0 w 224 448 560 448 0 c 128 176 64 176 0 1.9999999999999998E-4 0.0031726058186077504 w 128 160 128 176 0 w 128 176 128 208 0 o 12 64 0 35 0.009765625 9.765625E-5 0 -1 just copy past >.< ~wolf