I think the jtdm 8v is basically same engine as a jtd 8v wise but running higher fuel pressure (1600bar vs 1350bar)and maybe different injectors and more injection events per stroke, pilot pre and main plus 2 post events if dpf present. I think all 8v jtdm ive seen are 120hp.
I think the cf3 cf4 is on log book , think mine says either cf4 or euro 4.so id guess a jtdm would always be cf4 euro4
looked on an alfa workshop site and it lists for a 147 as example
Glow plug. JTD 8/10 valve glow plugs FOR CF2/CF3 models (BOSCH 0250202036).
and
Plug. Glow plug for CF4 8 valve engines (BOSCH 0 250 202 132).
should be able to cross reference in shopping site etc
most likely a slightly different current rating or afterglow time compatability to also reduce emissions