Fumarin

It looks like and airport crash rig
 

Hartson's!  That's a name I haven't heard in YEARS!  I remember the ambulance "station" on I-8 between El Cajon and La Mesa. As a kid I remember listening to El Cajon FD pre-Heartland days on a rotary tunable Radio Shack radio I had.  The El Cajon medic was "4391" and the chiefs/staff using 43xx but everything else was Engine/Truck - Back in the ALF days.  Then at some point the Ford C-Series Engine 6 became Rescue 6 ... Ah the good ol' days when you could listen to traffic on a tunable radio

I believe Medic #63 is still running out of Lindbergh (KSAN), because I have a friend who was on that rig recently.  I cannot answer your other questions, sorry.  Do you recall Medevac Ambulance, goes way back and they had contracts with San Diego Fire (-Rescue).  Who remember the presence of Hartson's Ambulance in San Diego?  When I was a kid, I recall they were in La Mesa, I believe, but real close to an on-ramp from Severin Drive, onto the I-8.  I'd see them rolling code coming down the on-ramp to get onto the I-8 going east.  I think back then, most the East County fire departments likely had Hartsons's as their EMT/BLS responses.  I believe Santee FD in conjunction with Lakeside FD, went operational with the first East County medic rigs ever, respectively Medic 4 and Medic 1.  They were sorta the pioneers of ALS/paramedics, modelled sorta after Los Angeles County's medics which the show EMERGENCY was all about (if I recall, I could be wrong).  Santee had been a very progressive department, with a rescue rig, even a HazMat rig they bought but never put into service as HazMat (it ran as a rescue, a GMC, as Rescue 4).  Santee has a technical speciality of trench/confined space rescue (if they still do).  I have not forgiven the chief and/or city council there for going away from the yellow painted rigs to the red.   ~Rescue51  

Maybe those are from National City and Chula Vista?

Looks like it was during training too

https://www.cbs8.com/article/news/two-firefighters-injured-in-training-exercise/509-434e4e59-254f-4b73-a058-fadbcae31b88
 

El Cajon ran a fleet of ALF engines (and maybe a truck?) when I was growing up there in the 80s.  Just seeing an ALF in El Cajon brings back memories

OK that was fantastic!  I noticed on the board they showed the equipment using what they use today - E5, T14, etc but when they dispatched them to a call it sounded like they were using 4 digit IDs.  I know when I first started listening to El Cajon in the late 70s / early 80s most of the county was using 4 digit IDs but did San Diego use them on a regular basis too?

Talk about a walk down memory lane - I do remember that!  From what seems like forever ago   Weren't they still using low band at that point as well?  (Before moving to UHF)