The easy thing to do, not what I'd do but the easy way would be to start Taylor wide, rest Merrin at 30mins about, move Taylor to lock then and replace Taylor with Merrin at about 60mins. You get an extra big guy in the middle and defensive specialist wide to start things, then can bring on Peach at 30mins when the defence is tired. In theory anyway, in reality the other team has replaced their players too so defenders are fresh and Taylor would be best at lock when our best front rower (Merrin) is providing him some staggered defence to use his footwork on. And Peach has been pretty great defensively, wouldn't gain much if anything having Taylor start wide instead of him.