just run it...
My 6.2 has sat for months without being started with no problems..but I do try to start it up and let it run at a fast idle for at least 15 minutes to charge the batteries,and keep the seals from leaking due to rust,etc,every few weeks....its important to keep it running at least 15-30 minutes to let the oil fully warm up,and burn off any condensation..also to keep the water thats formed in the cylinders from a cold start out of the crankase and exhaust system..
I think the "idle" isn't THAT important,unless its cold out,then you could get a buildup of carbon if one cylinder doesn't fire properly..diesels run rather cold at idle,and unburned fuel can collect on cylinders and pistons,and cake up with a tar thats like polished black walnut,and can't be removed..but in CA,I doubt you'll have that trouble this time of year...and you just rebuilt it,so it should be clean as can be..
Leaving the glow plugs out might encourage rust to form in the cylinders...
I've seen a diesel in a bucket loader,that just got used sparingly in cold weather removing snow,and idled a lot,with few oil changes..when the motor had noisy bearings after a few years,when they pulled the oil pan off,the only part of the crankcase that was not covered with thick ,hard,tarry goo was the crank and rods,and the space they chopped out in the tar!..I was amazed how good they were running when I saw that!!!....the stuff had to be chisled out with a hammer and chisel!..the oil pump screen was 80% clogged too,but it showed good pressure on the gauge!....shows how tough a diesel can be!..
