GPS Data to Garmin Instruments

I think that your best bet is a Garmin 19x NMEA 2000 GPS...

https://buy.garmin.com/en-US/US/shop-by-accessories/antennas/gps-19x-nmea-2000-/prod100702.html

... which seems to have a street price of about $200. It's a very good GPS and will surely work well with your instruments (assuming they can display GPS).

Meanwhile, the Actisense NGW-1 NMEA 0183 to 2000 gateway...

http://actisense.com/products/nmea-2000/ngw-1/ngw-1.html

...that you'd need to get the SH GPS to the N2K instruments cost almost as much and I think it's quite likely that the Garmin gear wouldn't accept the results as valid GPS. (There's a lot of data besides position in a full GPS stream and companies like Garmin are quite fussy about it, probably a good thing.)

However, other dedicated NMEA 2000 GPS receivers will very likely work with Garmin gear and you might consider the Lowrance Point 1 as it also delivers Heading info:

http://lr.factoryoutletstore.com/details/59991/lowrance-000-11047-001.html?category_id=20494

I don't know of any way to get iPad GPS onto a NMEA 2000 network and it doesn't seem like a reliable, accurate solution anyway.

Ben, thanks a ton for your feedback. You helped confirm some of the items I had already been considering, but the fact that the Actisense module would likely not feed the GPS data I want helps me cross it off the list. I'm not concerned about feeding the DSC data from the VHF.

I will look into a stand-alone GPS receive as you suggest and simply feed that into the NMEA 2000 network.

Thanks again!

i also need some suggestions about Garmin Instruments