An operator advances a delivery catheter through a guiding catheter, after positioning an inflatable sleeve of the guiding catheter in proximity to a target implant site on an epicardial surface. By inflating the positioned sleeve, the operator displaces the epicardial surface to create a gap that accommodates a reach of the delivery catheter. With the delivery catheter extending distally from the guiding catheter, the operator can activate the reach of the delivery catheter within the gap, and then advance the lead out through a distal-most opening of the delivery catheter. The reach may orient a fixation member of the advanced lead relative to the epicardial surface so the operator can secure the lead to the surface. The sleeve of the guiding catheter is preferably non-compliant and has a maximum diameter of at least twice the reach of the delivery catheter, when inflated.