  Let $k \leq n$ be nonnegative integers and let $\lambda$ be a partition of
$k$. S. Griffin recently introduced a quotient $R_{n,\lambda}$ of the
polynomial ring $\mathbb{Q}[x_1, \dots, x_n]$ in $n$ variables which
simultaneously generalizes the Delta Conjecture coinvariant rings of
Haglund-Rhoades-Shimozono and the cohomology rings of Springer fibers studied
by Tanisaki and Garsia-Procesi. We describe the space $V_{n,\lambda}$ of
harmonics attached to $R_{n,\lambda}$ and produce a harmonic basis of
$R_{n,\lambda}$ indexed by certain ordered set partitions
$\mathcal{OP}_{n,\lambda}$. The combinatorics of this basis is governed by a
new extension of the {\em Lehmer code} of a permutation to $\mathcal{OP}_{n,
\lambda}$.
