That spanner was used to install and remove the intake manifold tubes on Wright R-2600 radials also later on on Wright 3350s. Nadzab had both A-20s and B-25s which both had Wright 2600 engines. Below is an URL for a crashed A-20 at Nadzab.
Thanks so much for that info. It's been a long time wondering about it. It was strange that after 30 odd years when I picked up this spanner ( it was just sticking out of newly bulldozed ground) and other aircraft parts, they were in such good condition and only very minor surface corrosion. They were new parts ( and the spanner) so my guess this area was a stores deport bulldozed in after the war and rebulldozed up for the clearing of the present day Nadzab.
PS another part I could never identify from the same spot. I think a firewall forward part.