Anything is possible, but is it a good idea, no.
Look at GM's Olds diesel conversions. They were also a good idea but didn't work too well in the real world.
To do it right, it needs to start out being designed and built as diesel.
And to add a personal opinion, the A series is a great engine family for a gasoline engine, but I think that if one were able to successfully convert one to run on diesel, the stresses would cause one to self destruct.

Just wondering if the A15 could be strong enough
to run as a diesel using ARP bits and CA18de rods,
custom diesel forged pistons or other diesel slugs,
H89 head with filled in Combustions chambers and
re-angled valves and longer roller rocker arms.

Combined with a nice turbo and good rpm would be different