Lilly retired before Harrah came into NFL.

Mack had Lilly and Page. They were RDTs and he was a LG (except for 1971-72 when Rams went strong and weak guards under Prothro, but that is a different story)

Kent Hill had Randy White, who took over for Lilly (a couple years later, anyway)

Scibelli had Pugh, then Harrah had Pugh. Dutton took over for Pugh and that's who Harrah had to block.