P400 logical drive numbering scheme vs. boot order

[Falkens]

on a dl380 with p400 raid controller i have the following situation:
array A,B (single disk).
Now, A has LD#1 assigned and B has LD#3 assigned.
Question: how can I make the LD#3 to #1 because I want to boot from that disk (it appears that only from the lowest LD# can be booted if more than one LD is available at the same time.

or in other words: how can I change the LD number for a specific (physical) disk - and yes without destroying the data on it?

a scenario when this can happened is for instance if one restores a system disk which is created as e.g. ld#3 and then this disk shall be used for booting (insted the previous existing #1 {or C:}) but another ld#2 {e.g. as D:} is still available.

any hints are highly appreciated - I couldnt find the right doc which makes that scheme cler to me.

thanks in advance