My classic Ford Escort Kent crossflow engine block number shows: 681F 6015 - CA which tells me that it is a 1968 model with a 1300 cc engine. However, a small plate attached to the bulkhead shows: 89 /6015 BA. (See photo). The engine was rebuilt at one stage by the previous owner. Can anyone tell me what this plate means?

Hello, welcome to the forum
That plate looks home made or done by the mechanic/ engine builder once the replace rebuild was done for his own records in case the car came back for warranty etc.

Thanks for the information Marty.
Do you know if the plate indicates different specifications other than that already given on the block, and if so, what are they?

weird fonts even.
Doesn't say "i'm not a robot" anywhere below as well :)

A little bit of information, might not be exactly the answer your after but might help. With any luck someone with a little more knowledge can elaborate on what I've listed. 
 
681F 6015 CA
681F - Early X-Flow Engine (68 is the date which the cast was designed, not the date of the engine)
6015 - Ford Engine Block Part Number
CA - Variant of Engine (AA=1300, BA=1600, unsure about CA)
 
891M 6015 BA
891M - Unsure exactly what engine it is but the cast was designed in 89
6015 - Ford Engine Block Number
BA - 1600cc

Ford Kak motor , Endura ?? Not sure if they was 1600 but