new led drl for 2012 kia optima

I currently have a 2012 Kia Optima SX. It did not come with LED Daytime running lights. However, I have purchased and OEM model that is used in later car models. My car is not plug and play.

The LEDs that I have are able to run at 50% or 100%.

My plan is to wire them in so that when the ignition is on and headlights are off the DRLs with run at 100%. I would like the DRLs to switch to 50% when the Low beams come on. I would also like to add a switch inside the car (simple SPST) to be able to control them on/off when desired.

I have done a ton of research, including here over the last few days and have come to the conclusion that I need to use a SPDT relay to control the functions I need. The problem is that I don't have the training to put the wires in the correct location once I have the relay. I have found a few posts that have described what I should do but then I see others that contradict that.

What I think I need to do but would love it if someone could confirm or even throw me a diagram? Also, are their stores where I should and shouldn't buy these off the shelf (Pep boys vs. West Marine)?

30 goes to one side of switch and other post of switch goes to fused power source
85 goes to positive side of headlights
86 goes to ground
87a goes to high power or 100%
87 goes to low power or 50%

Thanks for the help. I am very mechanically inclined but very new to automotive relays and wiring. The knowledge on this site is unbelievable.
Mike

Relay circuit looks correct, as 30 and 87a are connected when the relay is not energized, thus you will have 100% when the headlamps are off.

SO, when you turn the headlights on, relay energizes, and power from Pin 30 then goes to 87 (relay is energized connecting 30 and 87), which will go to the 50% power to the DLRs.

TO hook up a switch INSIDE the car to manually use DLR:

Place a DIODE on the +12 from the headlamp source.
Run your desired (ACCY/IGN/+12) +12 source to the switch.
Place a DIODE on the output of the switch, wire to Pin 85 of relay.

You need the DIODE on the headlamp +12 source, so when you turn the switch on, the headlamp providing the +12 trigger does not turn on.

The DIODE at the switch is not really necessary, but is a safety measure, JUST in case.

Don't forget to add fuses in line with each power source.

+12(5A FUSE)(PIN 30 RELAY)
+12 from headlamp--(1A FUSE)(DIODE)->(RELAY PIN 85)
+12--(1A FUSE)(SWITCH)(DIODE)->(RELAY PIN 85)

IF you have questions about diodes, the stripe faces the direction of flow.

The Power to pin 30 fuse, rated at the operating amps of the DLR LEDs.

The trigger power source fuses can probably be 1AMP. The coil does not need a lot of current to energize the relay. You do, for sure, want fuses from the headlamp, and main power to PIN 30. From the switch? Precautionary...