Never top a spruce tree, or any other tree for that matter. The only trees I consider topping are small, overgrown ornamental trees where the only other option is removal (crown-reduction pruning isn't generally viable on small ornamental trees), or arborvitae (which are technically a shrub), and trees that have a lot of dead in the top section as a last-ditch attempt to rejuvenate the tree . Even in the limited subset of cases I will top a tree (except for arborvitae), I warn the customer that it may shorten the trees lifespan, that it tends to produce excessive, weak shoots that will break off in storms, and that it may lead to significant decay problems at the juncture where the topping was done. The only option I'd recommend for these trees would be to let them be, or remove them. Either way, it's the land-lady's decision, not yours.