The remapped ECU for my son's 1999 TD5 90 has just arrived from Stormtuning. I was planing on installing it and using my Hawkeye Total to map the injectors. However, Stormtuning are saying that I also need an adapter in order to recode the security. I was not aware the was required, pretty sure the 90 does not have a BCU.

Can anyone shed any light?

if original ecu from his truck got sent off then storm usually just sends out another ecu. I took mine to him for my td5 disco and he took an already done ecu out and swapped it for mine, that needed the security codes learning with a nano com to get it to work but for a 90 id assume plug and play. He knows his stuff, try it and see if it starts as no bcu on a 90, I'm just putting in a 15p td5 into my G reg 90 and last friday managed to get it running if only for a few seconds before it cut out (assumed fuel issue) but i haven't even programmed the green top injector codes into that msn ecu and it started up.

Thanks Robbie, plug and play was my assumption as well. I guess we just try it and see.

So we plugged and it played.
Programming the injectors was a doddle and there was no requirement to re-learn security codes on such an early TD5. We did need to get it to learn the 2 track throttle input though which we had not anticipated. Neither of us knew which system, 2 or 3 track was installed, but a quick google suggested that 3 track came in at 2002, so 2 track was a reasonable, and correct assumption. At first it refused to relearn and we wondered if it was faulty; however, there was a tiny trace of oil in the Red plug (we replaced the injector harness about 2000 miles ago) so we flushed it with brake cleaner and the problem went away.
Significant change in performance, not life changing perhaps and the gearing ratios still make 70 on the motorway a bit of a strain, but low and mid-range torque seems much better and it now easily keeps up with modern traffic, making it a much more practical only car for my son. Time will tell if he can be restrained enough to reap any economy benefits, or whether he will just burn the fuel putting a smile on his face.

happy days. Would it start at all with the throttle settings on 3 and not 2 or would it just not run?

We did a quick experiment initially as it was set to 3 track on arrival and as a 10P non-flashable ECU, we assumed it was set up for a 10P truck.
Started and ran fine, but no throttle response.