src - As Bill said, pull the switch (it's a really simple job) and Google the number or ask here. Monaco changed things around a lot over the years.
I was too lazy to actually look at mine, and just went off what someone with a different year coach said when I ordered one. And, of course they changed in between
Haven't had the opportunity to tear up my propane system 'yet', but the number may be on the regulator itself.