ADL3 -- Clock from GPS Time

[Digitalwave]

Hello all,

I have a new-to-me car that has an ADL3 with all options unlocked. I'd love to add a basic clock to one of the dashboards. The dash has a Motec GPS module that receives a GPS Time channel in HHMMSS.sss format. I'm lost with trying to turn that into a local (U.S. Eastern time) time format that I can add to the dash.

From what I can tell this is going to take several advanced maths equations, especially since I have to convert the time zone. The other twist is that the amount of digits for the received GPS Time signal changes since it's in UTC 24 hour format.

00:01.01001 is received as "0101.001"
01:01.01001 is received as "10101.001"
11:01.01001 is received as "110101.001"

If anybody has figured this out already and can share their maths, I'd greatly appreciate it!